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10 Apr 2009

RB Usage, Part I

Guest column by Mike Horn

"In our league, you're seeing less and less of that one back, that [one] guy doing it all the time," Sparano said. "I mean you can look around the league and really see that's something that doesn't last very long because of injury, and because of how good the other people are."

-– Miami Dolphins coach Tony Sparano, quoted in the South Florida Sun-Sentinel, April 2, 2008

Every so often, some talking head or coach will go on about the increased use of a "two-back" system or some other method of employing running backs. Usually these comments center around the way a few teams that have just made the playoffs use their running backs. The commentator claims this is now a "trend" without any real analysis of what has gone before. I'll wonder, are there really more teams using "two backs" now than there were? Are fewer teams using a committee approach or one heavily-used runner? Can the evolution of NFL running back usage be quantified? This is my attempt to answer those questions.

Caveat Lector

I decided to begin my study with the 1960 season. Like any start date, this is arbitrary. The founding of the AFL that year and the NFL's reactionary expansion marked a clear change from the small number of teams playing in the '50s to the much larger major league pro football of the '60s and beyond. I felt therefore that 1960 was a good point to start analyzing running back usage.

There are other key years that could have been chosen: the full NFL-AFL merger in 1970, the rules changes to increase offense in the late '70s, the start of the 16-game schedule in 1978, adoption of full free agency in 1994, etc. And there are the strike years of 1982 and 1987 to factor into the story. As necessary, I'll address all these dates, but I opted for the earliest date in order to maximize the length of time studied and to show how the game evolved from the '60s into the rushing-heavy '70s and beyond.

I'd love to use advanced statistics to tell the story. Unfortunately, FO's DYAR and DVOA don't go back as far as 1960. I decided to use rushing attempts and running back receptions as the key statistics to analyze usage patterns. Perhaps success-related numbers like yards or yards per attempt would have been better than activity numbers, but I stuck with carries and receptions as more indicative of usage.

Terms

There are lots of terms that get thrown around when discussing running backs. Two traditional terms are "halfback," which has fallen out of use, and "fullback," which persists. But the 21st-century fullback bears no relation to the fullbacks of the 1960s. Perhaps the greatest running back of all time, Jim Brown, has "fullback" listed in his statistics chart at Pro-Football-Reference.com. A history of the fullback position and its evolution might be interesting, but that's not what I'm writing. I'm going to treat both fullbacks and halfbacks as running backs for this analysis. I'm also going to consider I-backs, split backs, H-backs, and any other term descriptive of where players line up in formation simply as running backs.

I will use the term "lead back" to indicate the running back who had the most rushing attempts on a team in a given season. I will also refer to the lead back as the RB1. "Second" running backs, or RB2s, will likewise be the running backs with the second-most carries on their teams. Note this is a purely statistical description; often a team's RB2 will have been its intended starter or will have started some number of games, but injury or ineffectiveness caused him to get fewer carries than the "lead back." And in the '60s, at least, the RB2 may have actually played a different backfield position than the lead back and not been his alternative or backup at all. I am not trying to figure out intent, which would be a much longer and more detailed study, just actual usage. Similarly, "reserve" running backs will be those with the third-, fourth-, fifth-, etc., most carries -- RB3, RB4, RB5, and so on. The 1970 Saints had an RB13, Claxton Welch, although he had zero carries, as did Gary Lewis, the RB12 by virtue of the alphabet, while the RB10, Bill Dusenbery, and RB11, Earl Gros, had four rushes each.

I'll introduce and define a few more terms later, but for now let's look at how the lead back's role has changed.

Lead Backs

First, running back rushing attempts per team in 2008 (24.4) are not that different than they were in 1960 (26.3) or 1961 (25.2). Obviously, the graph below shows there have been a lot of changes in between to get back to this point.

From 1961 on, there was a relentless increase in running back rushes per game until they peaked in 1977 (34.4), when the league began to change the rules to favor passing more. This had the desired effect, and the league returned to 1961 levels of running back rushing attempts by 1989 (discounting the 1987 strike year low point; for some reason, the strike years both fell below the trend in RB rushes, although not significantly). In 1990, the NFL dropped below an average of 25 running back rushes per team per game and has not gone above that mark since. It has stayed generally flat around 24.5 since then, with a low point of 23.5 in the 2000 season. How have those carries been divided up?

The next chart shows the breakdown of overall NFL running back carries. For each season, the RB1 rushes were summed and then divided by the total number of RB attempts. While this hides a lot of individual differences across teams, it should capture general trends. And it clearly shows the increased reliance on one lead back to carry the load from about 1980 on.

Meanwhile, second RBs saw a gradual decline in their share of the carries from 1970 to 2000, with a slight upward trend since then. RB3s have half the share of rushes (8 percent) that they had in 1960 (16 percent). And the rest of the backs on NFL rosters, who for a while from the late '60s to 1980 collectively carried the ball as often as RB3s, now make a token 5 percent of the league's rushes.

The next table breaks the data into three periods, with the minimum and maximum percentages of the total running back rushes that each of the various types of RBs received in those time spans:


Ranges of RB Rushing Shares
Seasons RB1 RB2 RB3 OTHER
1960-1980 42-48% 26-31% 13-16% 10-16%
1981-1993 50-59%* 23-27% 11-15% 6-14%
1994-2008 60-70% 19-27% 6-10% 2-6%
*Omits the 1987 strike year share of 48%

From 1960 to 1980, lead backs as a group never got more than half the league's rushes. Since 1980, they've never gotten less than half (except in the strike year of 1987 when the use of replacement players naturally spread the carries around more). From 1981 to 1993, RB1s never handled more than 60 percent of the total running back carries. And since the dawn of full free agency in 1994, RB1s have never seen their share fall below that mark (although in 2008, they dropped to that level).

Meanwhile, RB2s have gone from getting 25 to 33 percent of all carries from 1960-1980, to around 25 percent in the middle period, and then to 20 to 25 percent after 1993. They have only climbed back above 25 percent in the last two seasons, with 27 percent in 2008 -- not coincidentally, when the RB1 dropped to 60 percent. Reserve backs (RB3 and Other) also made 25 to 33 percent of the rushes (about the same total share as second RBs) in the '60s and '70s, then fell to less than 25 percent in the 1981-1993 time frame and to no more than 15 percent from 1994 on.

Basically, when NFL offenses had two true running backs in the backfield, one got most of the carries, another got some, and their backups shared the rest. But as offenses decreased the rushing responsibilities of one back (the fullback) and the run-blocking role of the other back (halfback, tailback, etc.), the rushing share of the lead back increased. The RB2 became more of a backup or change-of-pace player who substituted for the lead back instead of being another runner on the field at the same time as the RB1. In turn, this meant the "reserves" (by my definition in this study; the blocking back who got a few carries was of course also a starter in the actual line-up), instead of sharing the carries destined for two runners in the formation, were now getting only a few leftovers plus some opportunities when the top two backs got hurt.

A turning point may have been reached in 2002, when lead backs made a fraction under 70 percent of all the rushes in the NFL. For the next four years their share hovered around 65 percent before dipping to 61 percent in 2007 and 60 percent in 2008. It remains to be seen whether this is a true change in running back usage or just an anomaly, but the fact that it has happened two years in a row may mean that change has come.

Also, it's important to understand that while lead backs have seen their share of carries increase, their total number of carries per game played (which factors out schedule length and number of franchises) hasn't changed as dramatically:

Lead back usage in the '60s was flat, around 12.5 carries per game. Then it climbed to a plateau around 14 per game in the running-dominated 1970s and to around 15 in the early 1980s. After a drop below '70s levels from 1986 until the free agency period, it has held steadily above 15 until the past two seasons. But the real change has been more the decline in total running back carries since 1977 than an increased reliance on RB1s as a group. Looked at this way, 2002 doesn't stand out as a turning point in lead back usage, but 2007 might be.

Workhorse Backs

What about those runners who carry a very heavy load? I think everyone knows they are a lot more prevalent than they used to be, but has that shifted at all in the last few years as Coach Sparano seems to claim?

First, I want to define how I'll use the term "workhorse" back. Obviously, 370 rushes was going to be too many. Not many running backs reach that workload, and the Curse of 370 ensures that not many do it very often. Because of the different season lengths in the period studied (12, 14, and 16 games, plus the strike years), I decided on a per-game count rather than a season total. Twenty carries per game was a nice round number that seemed like a heavy load week-in and week-out but didn't approach the accursed 370 for a 16-game season. This study will consider a "workhorse" back to be one that got 20 carries per game.

The first NFL workhorse was Steven Van Buren, of the 1949 Eagles, followed by Eddie Price of the 1951 Giants. Then there was a lull of several years until Jim Brown did it in 1958. The next chart shows the percentage of teams (rather than number of teams, to factor out expansion) that have employed a workhorse back in every season since 1960.

Brown was the first back to be a workhorse for an extended period of time, notching six total workhorse seasons in his career. Jim Nance of the '66 Patriots did it the year after Brown retired, and then there were no workhorses again for several years. The '60s (the red line on the graph) were still the pre-workhorse era.

The 1970s saw the dawn of the first workhorse-back era. Matt Snell ('70 Jets) broke the 20 carries per game barrier, but in only three games. There then was a gradual increase in workhorse backs over the next decade that peaked in the early to mid-'80s followed by a decline until 1990 when there were none, ending the era (blue line).

In 1990, it would have been easy to think that the day of the workhorse back had ended, probably because it was too hard to keep them healthy. In fact, it was the start of what looks like the golden age of workhorse backs.

The second workhorse back era started in 1991 (green line), when Emmitt Smith met Norv Turner, Barry Sanders had his first workhorse season, and Gaston Green had his one-time experience with a heavy workload in Denver. From that year on there was a steady increase in teams using workhorse backs until 2003, when more than 40 percent of teams employed one. Now the league appears to be moving away from that method of using running backs, although obviously it's too soon to tell if this is a permanent change.

The next chart takes the data above and plots it as trendlines (second order polynomial). If the current trend is consistent with previous examples, the use of workhorses will decline for a few to several years and then revive. It might even peak at a higher level next time.

There have been 89 backs who have combined for 200 workhorse seasons since 1960. But almost half of those have been produced by only 17 runners. There were 47 running backs, like Gaston Green or Jim Nance, who only sustained this type of heavy workload for one year.


Distribution of Workhorse RB Seasons
Career WH Seasons No. of RBs Total WH Seasons
4 or more 17 93
3 10 30
2 15 30
1 47 47
Totals 89 200

The "true" workhorses, those with four or more seasons with that type of usage, started with Jim Brown. There were four in the first workhorse era and twelve in the Golden Age:


Workhorse RBs by Era
1960s '70s and '80s '90s to present
Jim Brown (6)* Walter Payton (8) Edgerrin James (8)
Eric Dickerson (7) Emmitt Smith (7)
Earl Campbell (5) Curtis Martin (7)
O.J. Simpson (4) Eddie George (6)
Barry Sanders (5)
Jerome Bettis (5)
LaDainian Tomlinson (5)
Clinton Portis (5)
Stephen Davis (4)
Shaun Alexander (4)
Priest Holmes (4)
Ricky Williams (4)
Number of Workhorse seasons in parentheses; *Jim Brown includes workhorse seasons prior to 1960.

In fact, it has been the number of true workhorse RBs that has set the "Golden Age" apart from the '70s and '80s. If those backs are taken out of the data, the period from 1970 on looks pretty much the same: About 10 percent of the teams in any one year will employ a workhorse back if they don't have one of the backs named in the table above. That is shown by the dotted black line in the next chart, which excludes the true workhorses. There was a small increase in 20-carry-per-game seasons among other backs from 2003 to 2006, but the fact that eight of the 17 true workhorse runners were posting high workloads in that span is also a factor in the spike during that period. Excluding the true workhorses, 2007-2008 look to be more in line with the running back usage pattern of the entire period from 1970-2006 -- in other words, it may be a regression to the mean. Or it could be that several teams tried the workhorse system in 2003-2006 and found that it didn't work without a true workhorse -- which might be hard to find. This would support Coach Sparano's statement.

The Workhorse Whisperer

Norv Turner broke into the NFL coaching ranks with the Los Angeles Rams in 1985 as a receivers coach. He got to see first-hand one of the foremost workhorse backs in NFL history, Eric Dickerson, the Curse of 370 exceptionaire. Norv apparently was strongly affected by this. When he became an offensive coordinator, and later a head coach, he became the foremost user of workhorse backs.


Norv Turner's Lead Backs Per Game
Year Rushes Rec Touches
1991 22.8 3.1 25.9
1992 23.3 3.7 27.0
1993 20.2 4.1 24.3
1994 11.6 3.2 14.8
1995 21.1 1.9 23.0
1996 21.7 2.0 23.7
1997 21.0 2.0 23.0
1998 14.8 1.7 16.5
1999 20.7 1.6 22.3
2000 22.1 2.2 24.3
2001 21.2 3.7 24.9
2002 23.9 2.9 26.8
2003 24.5 3.1 27.6
2004 10.6 2.6 13.2
2005 19.4 5.0 24.4
2006 19.5 3.8 23.3
2007 19.7 3.8 23.5
2008 18.3 3.3 21.6

Dual Running Backs

So far, it looks like in recent years there have been drops in the share of the rushing load carried by lead backs, and in the number of workhorse backs. Those declines may be temporary, or they may be real changes in the way running backs are used, but they have occurred. It is often suggested that teams are adopting a two-back system as an alternative. First, what is a two-back or dual-back system? And second, has it become more prevalent throughout the league?

I developed three criteria to describe a "dual RB" team. First, the RB1 and RB2 on a team had to combine for more than 85 percent of the team's runs by running backs. This indicates that a team relied on two players as opposed to a committee for the vast majority of its running game. Second, the RB2 had to have at least a third of the team's total RB carries. This screens out teams where the RB1 got a huge percentage of the carries and the RB2 got very few. Earlier we saw that the league average share for RB2s has never been more than 31 percent, so this is a pretty high number, but it does allow some flexibility in letting teams qualify. Finally, the sum of the RB1 and RB2 games played had to be more than 80 percent of their possible appearances; for example, in a 16-game season, they had to combine for 26 game appearances out of a maximum of 32. In combination with the other criteria, this screened out almost all times when a team had an RB1 get hurt and just used his backup as a surrogate RB1 as opposed to sharing carries between two main rushing options.

I then identified recent teams that struck me as employing dual RBs: the Vikings, Jaguars, and Panthers in 2007; and the Saints, Colts, Bears and Patriots in 2006. When tested against my definition, all passed. So I felt comfortable that this was a reasonable if not perfect description of teams that used dual running backs, although it probably excludes a few teams who were genuinely trying to use two runners.

The chart below shows that dual running backs have been used throughout the period since 1960. Their heyday was from 1964 to 1972, then this usage fell out of favor for more than a decade. (Even the dual-back system of the champion 1976 Steelers, with two 1,000-yard rushers, did not inspire a revival, although the rule changes in the late '70s probably affected that.) From 1985 on there has been a general upward trend in the percentage of teams employing this system (the black line shows the trend across the entire period). The strike year of 1987 was the last time there was no dual-RB team.

Of course, the modern dual-RB system basically consists of alternating tailbacks, only one of whom is in the lineup on a given play, while the '60s version was a fullback and halfback on the field at the same time, either of whom could get the ball. This required the halfback to be able to run-block to some extent, a requirement lacking for the modern tailback. Which is why for all the talk by coaches employing dual-RB systems of playing both backs simultaneously, there rarely is a time when two tailbacks are in the backfield together. Which one would block for the other? So while the net effect of two backs sharing rushing attempts has come back, the old methods have not.

There has been a definite spike in dual-RB teams the last three seasons, as 2006 to 2008 saw the first three seasons where more than 20 percent of teams used dual running backs. In fact, as the next table shows, there were more than twice as many dual-RB teams from 2006 to 2008 as in the 11-year period from 1974 to 1984. The minimums and maximums in the table refer to the lowest and highest percentage of teams using dual running backs in a season during the relevant period.


Distribution of Dual-RB Seasons
Years Teams Dual RBs % Dual RBs Min Max
1960-1973 336 38 11% 0% 19%
1974-1984 304 11 4% 0% 7%
1985-1995 310 28 9% 0% 14%
1996-2005 311 36 12% 6% 17%
2006-2008 96 23 24% 22% 28%

Aside from 1974-1984, and the last three years, the other three periods shown in the table were generally consistent with each other. It remains to be seen whether 2006-2008 marks the start of a new period with much wider use of a dual-RB offense or whether the league will regress to its long-term mean of 10 to 12 percent of teams employing two backs, but the recent trend seems very strong.

Over the entire period, there is almost no correlation (0.07) between the percentages of teams using workhorse backs vs. dual RBs. From 1970 on, when the workhorse system began to be used by teams not employing Jim Brown, there actually is a slight positive correlation (0.20) between the two methods. In the free agent era (1994 to present), there has been a more noticeable negative correlation (-0.44), indicating that the there may be a competition between the two systems. But historically there has been room for both in the league. In fact, over the last 38 years, the combined use of those two systems has been increasing:

Well, if those two usage methods have gone up, what has gone away? That will be addressed next week in Part II of this essay.

Mike Horn writes a stats-based column for FantasyGuru.com. In real life he is a retired Army officer working as a military defense analyst in the Washington, DC area. He occasionally comments as MRH on Football Outsiders discussions and has written two previous guest articles on tight end usage and how teams used draft picks over a five-year span. If you are interested in writing a guest column for Football Outsiders, please send an idea or rough draft to info-at-footballoutsiders.com.

Posted by: Guest on 10 Apr 2009

38 comments, Last at 16 Apr 2009, 9:24am by mrh

Comments

1
by Jimmy :: Fri, 04/10/2009 - 11:05am

Wow that's thorough.

2
by bubqr :: Fri, 04/10/2009 - 11:06am

Very interesting article. Looking forward to Part 2. Nice job.

3
by johonny (not verified) :: Fri, 04/10/2009 - 11:27am

I was thinking that increasing the season length would be the death of the workhorse back for good. But according to the data the last time this occurred the exact opposite happen. So possibly increased season length plus even more liberal passing rules might allow the workhorse back to remain somewhat a part of the game in a 18 game season. Interesting stuff.

12
by panthersnbraves :: Fri, 04/10/2009 - 4:04pm

By the end of the 2005 season, the Panthers had pretty much run out of RB's... Expanded seaons -> expanded rosters and expanded cap.

4
by Tom Gower :: Fri, 04/10/2009 - 11:36am

Interesting piece.

Basically, when NFL offenses had two true running backs in the backfield, one got most of the carries, another got some, and their backups shared the rest. But as offenses decreased the rushing responsibilities of one back (the fullback) and the run-blocking role of the other back (halfback, tailback, etc.), the rushing share of the lead back increased.
This seems plausible, but actually showing it seems like it gets a little too much in the history of the fullback position-call it an underproven statement.

That 1970 Saints team is weird-2-11-1, but wins over 10-4 playoff team DET (6 TOs, plus Dempsey's "63" yarder to win) and 9-5 NYG (winning TD on fumble recovered in EZ by WR), and a tie against 10-3-1 playoff team SF.

5
by Chris (not verified) :: Fri, 04/10/2009 - 11:39am

Nice to see a regular and fellow Washingtonian post an intelligent article.

So why the recent spike in "dual RB committes".
A) Copy cat league, teams copying SB champ Indy...
B) Short lived trend
C) There is a plethera of talented RB's in the NFL, and the difference in talent between RB 1 and RB 2 doesn't outweight the fatigue, injury risk, risk of having to change your offensive identiy, or having huge salary demands after putting up big aggregate numbers or the benefit or perceived benefit of having a "change of pace" back to mix it up.
D) All of the above
E) None of the above.

Chris is going with "C" or maybe "D".

21
by Yaguar :: Sat, 04/11/2009 - 12:44pm

I like C. The difference between RB and other positions (QB especially) is the depth of the talent available there. Obviously, there are only a handful of them as good as DeAngelo Williams or MJD, but if you have a fairly average starter, it's not too hard to find a backup who is almost as good as him.

A good way to show the depth of the RB position: Imagine that your team has to use a street free agent type for a couple of games. Is it going to be awful? Nah, not really. You can survive with your team using Peyton Hillis or Darius Walker or something. They'll be happily mediocre. Sure, there are occasional mind-bogglingly awful players like Chris Perry, but they're the exception rather than the rule. At most other positions, though, if you have to sign and play some street guy, the average street FA is in for a rough time.

24
by mrh :: Sat, 04/11/2009 - 2:26pm

thanks Chris. My original suspicions were A or B but by the end (and there's still part II to come), I leaned C or D. Actually, I started out believing the dual-back "trend" didn't exist but the data seems to prove me wrong.

I originally drafted this last year but it needed some editing; between my schedule and FO's it wasn't ready last off-season. So when Aaron got ready to post it this year I updated it with 2008 and another year of data makes it appear more likely the trend is real.

6
by Howler37 :: Fri, 04/10/2009 - 12:18pm

Initially, an extra two games probably won't kill the workhorse back, but his career would probably be shortened. You're basically using him up faster, and he might well get an injury which will drop him from being the #1 back. You're not going to see a long career; much has been made elsewhere about where LaDanian fits as far as career goes.

14
by johonny (not verified) :: Fri, 04/10/2009 - 6:02pm

I agree. About the only thing that can save them is going to an even more pass oriented game in which running back carries per game drop. Which may happen given the new passing rules they are putting in place.

7
by TerryW :: Fri, 04/10/2009 - 12:47pm

This is outstanding analysis. Reminds me very much of, honestly, a consulting firm's work - McK, BCG, ACN, etc. Digging the graphs and the precise explanations of requirements (such RB2 needing 1/3 of the carries).

8
by Chris (not verified) :: Fri, 04/10/2009 - 1:36pm

Except the folks at McKensey do that work for money, while our friend Mike Horn did it for the good of football academia.

I like the part, Mike Horn writes a stats-based column for FantasyGuru.com. "In real life ..."

9
by Kevin from Philly :: Fri, 04/10/2009 - 2:18pm

Now I remember why I hated Stat class back in college - my head is swimming. Good thing this came out on Friday, so I can let beer clear my troubled mind.

10
by brodelicious (not verified) :: Fri, 04/10/2009 - 2:33pm

I would be intersted to see the data on the recent Chicago Bears teams.
I would think that it would prove an interesting case study. Mostly showing that dual running back teams versus workhorse teams depend completely on personnel. Not some sea change in overall scheming.
When Thomas Jones and Cedeic Benson split carries it was because neither set the offense on fire.
Last year Forte became the workhorse because either A) He was extremely talented. Or B) There was a significant dropoff in talent from first to second string.
It seems that workhorse backs are just as elusive as franchise QBs.
The next question needs to be whether a workhorse is as essential to team success as said franchise QB.
Perhaps GMs and coaching staffs have discovered that the financial payout for one workhorse running back is not justifiable.
Is it less costly to go dual rb and is it as effective in producing wins?

11
by vherub :: Fri, 04/10/2009 - 3:22pm

Look at the names-
If a coach has a special talent, a James Brown, Dickerson, Payton, OJ, or Tomlinson, you want to get that guy as many touches as you can. Any good coach that finds a HOF caliber runningback on the team is going to give him the ball. It just makes sense. A few of those guys on the 90/00s list are not HOF guys, and that could be teams trying to imitate without having the right ingredients. But I think future trends will be based on how lucky a team is to have a supremely gifted and durable runnningback.

29
by Bobman :: Sun, 04/12/2009 - 12:52am

Not necessarily. I am expanding your second sentence to basically mean give your best player the ball. If you look at the leaders in career workhorse seasons, you see Payton (no explanation needed) but also Edge James. Well, I am as big an Edge fan as anybody, but you'd think that giving gthe ball to the surefire HOFer (Manning) makes more sense than giving it to James (HOF potential) so much. IIRC, there was one season when James was the ONLY RB to record a carry for his team. Is that possible? Maybe I am mistaken, but I will bet there are at least 2-3 seasons when he recorded 95%. Clearly it worked, but just as clearly, it only worked so well and then hit its limit down the stretch and in the post season. They didn't win the SB ONLY because they went to a platoon, but having fresh legs through week 20 proved to be very helpful.

Just an awesome article, BTW. Thanks.

30
by Bobman :: Sun, 04/12/2009 - 1:39am

Okay, so I was wrong about Edge having 100% of RB carries one year. In 1999 he had 369 and Keith Elias had 13. 96.6%

In 2000, he had 387 and Lennox Gordon had 4. (Finn and al-Jabbar each had 1) 98.5%

In 2001 he had 39% of rushes but played in 37% of the games--Amazing that Tom Moore and Manning fed Rhodes the ball as much as they did James. Rhodes, who replaced him, was an UDFA rookie--but he got 1,104 yards in 10 starts, with a similar carry rate to that of his lead back.

After Edge's injury, they tended to sub in guys more, either for a few carries a game or a whole game while Edge sat. It looks like he rang up 75% of RB carries ever after in Indy. Which is still crazy when viewed against the historical data.

2006 in AZ, back to his old tricks: 89%. 2007: 89%

Back in the land of the blue horseshoe, they have one near-elite back and one savvy veteran. In 2006, only 2 RBs touched the ball and Addai/RB1 carried 55% of the time despite never starting. Good success. The next year they lost Rhodes and Addai platooned a bit, but started and saw 63% of the touches. 2008 does not merit inclusion. So as a team and with their personnel, they went from almost insane purity of workhorse philosophy to a moderated but still 1-back-heavy plan, to a relatively balanced pair of guys. The evolution will be interesting.

Note: Tom Moore, the OC in Indy for the past decade, also ran a pretty notable one-back system in Detroit with a guy named Sanders.

13
by Chris (not verified) :: Fri, 04/10/2009 - 4:34pm

I think Thomas Jones was better than people gave him credit for, and he was a good fantasy pick for me where ever I drafted him. I'd agree with your analysis though.

Are there more duel threat RB's because teams have two good RB's and that is because there are a lot of talented RB's in the NFL and the talent level at the margin isn't that different.

If I had RB A that was a 89/100 and I subbed him in for a RB that was 87/100 with a little bit different skill set, that makes sense. If have a RB that is 89/100 and let him work horse it because the next best alternative is a 71/100 that makes sense as well.

I think two interesting examples to throw out there are the Dom Rhodes/Addai example in Indy a few years ago, Julious Jones/Marion Barber, Tomlinson/Turner or Earth/Wind/Fire.

16
by brodelicious (not verified) :: Fri, 04/10/2009 - 8:52pm

I totally agree about Thomas, in the sense that he is far better than most people give him credit for. But I think most would agree that he was closer in talent level to Cedric Benson than Kevin Jones is to Matt Forte. I guess I'm just wondering whether a team chooses to go dual depends not on the talent of the first string back, but the gap in talent between first and second string.

32
by Jimmy :: Sun, 04/12/2009 - 10:25am

I read some comments from the Bears coaches that the reason Forte got almost all of the carries was because once Benson went a'boating they had to get Forte up to speed with all of the offense which meant giving him as many training camp reps as possible. That meant guys like Kevin Jones and Garrett Wolfe couldn't be gotten up to speed with the offense (apparently). Switching QBs every day can hardly have helped matters either.

15
by matthewglidden :: Fri, 04/10/2009 - 6:10pm

The article compares Dual and Workhorse RBs over time, but it'd be useful to include composite W/L outcomes of games that feature each approach. Though teams run more when they're ahead, the strategy of RB use could (should?) vary less over a full season. If one approach proves superior over time, you could move from it to a more detailed search for how defenses react to one vs. multiple runners.

17
by BDAABAT (not verified) :: Sat, 04/11/2009 - 12:00pm

Mmmm.... regarding workhorse backs, what about including the last +2,000 yard rusher in a season...Jamal Lewis? Yes, he had a fullback with him, but he got the lions share of the workload.

Bruce

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by Rich Conley (not verified) :: Sat, 04/11/2009 - 12:05pm

". This indicates that a team relied on two players as opposed to a committee for the vast majority of its running game. "

Why isn't the commitee being measured? Its just an extension of the multiback system.

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by Rich Conley (not verified) :: Sat, 04/11/2009 - 12:05pm

". This indicates that a team relied on two players as opposed to a committee for the vast majority of its running game. "

Why isn't the commitee being measured? Its just an extension of the multiback system.

23
by mrh :: Sat, 04/11/2009 - 2:18pm

see part II when it gets posted.

Part II will deal with RBBC, 3rd down backs, and have a little analysis of the connection between RB system and winning/offensive success, including a little about the recent Bears' dual back system.

20
by Rich Conley (not verified) :: Sat, 04/11/2009 - 12:10pm

Just a note: The double post above, the first time it told me the captcha token was wrong, so something isn't working correctly.

22
by Felton (not verified) :: Sat, 04/11/2009 - 1:34pm

I wonder if the spike in workhorse RBs stems from a lack of continuity in the game. 40 years ago, player movement was almost non-existent and teams stayed together. Offenses could be more intricate, where two backs could be a running option in any formation. In the modern era, continuity is almost non-existent and teams have opted for offensive schemes that require little or no timing and coordination. Hand the ball to a back, let the line puah and let the back find a lane. Three-step drop and pass to the best receiver.

25
by tuluse :: Sat, 04/11/2009 - 2:54pm

In the modern era, continuity is almost non-existent and teams have opted for offensive schemes that require little or no timing and coordination.

Do you really believe this? All evidence points to offenses becoming more and more complicated.

26
by Jerry :: Sat, 04/11/2009 - 6:19pm

I think it has more to do with the trend toward specialization. Teams seem to feel that they're better off with one guy to run (+/- all the stuff that Mike is describing so well) and another who's like a third guard than two who can run and maybe not block so well.

27
by Chase (not verified) :: Sat, 04/11/2009 - 8:39pm

First let me say this is a terrific article. Great job doing a bunch of research on the issue.

http://www.pro-football-reference.com/blog/?p=1886 -- there, Doug talks about how James Wilder issued in that new era of workhorse backs. Worth a listen if you've got the time.

One other thought on the evolution of the running game. Starting in the '90s, RB fumbles plummeted. In 1981, the top 10 RBs by carries fumbled 2.8 times per 100 carries; by 1993, that number had halved to 1.4. The next year, it was 0.9. As teams found that RBs could handle a bunch of carries and not fumble, two forces converged to increase the number of carries for RB1s. One, late in games, the starter would continue to get the carries because his skill at not fumbling was essential to run the clock. Two, I think teams changed the way they viewed wear and tear -- a guy might be considered likely to fumble after getting hit 20 times in a game, so they used to limit carries. Now, though, the worry was that bringing in a cold body off the bench was riskier than keeping the ball in the hands of a sure handed running back. As coaches became more risk averse as the reach of the media expanded, "losing" with your star was much more acceptable than having your backup cost you the game.

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by mrh :: Mon, 04/13/2009 - 10:13am

thanks.

Interesting that using Doug's measure of a "workhorse" (my term, not his), getting 90% of a team's touches, show the same pattern as my measure (20/game) of a peak in the mid-80s, a decline, and then a rise again in the early '90s.

The fumbles numbers are very interesting.

Re Wilder and John McKay. Once, after O.J. Simpson carried the ball 47 times in a USC game, McKay said: 'He doesn't belong to a union. Anyway, the ball doesn't weigh that much.'

28
by ChicagoRaider (not verified) :: Sat, 04/11/2009 - 10:00pm

Marcus Allen apparently did not have as much as 4 workhorse seasons. That surprises me.

34
by Lance :: Mon, 04/13/2009 - 1:31am

I was thinking something similar about Tony Dorsett. But doing the quick math, he averaged just 17 carries a game over his career. Definitely not what I had expected...

31
by DoubleB (not verified) :: Sun, 04/12/2009 - 9:42am

I'd argue the rise in workhorse RBs has at least something to do with a change in basic scheme. How many split back running games were there in the NFL in the 70s? Based on the Super Bowl games of that era, possibly everyone. Today, I can't think of one team that has a legitimate split back run scheme. It's all one-back, true I, and offset I. Scheme-wise it's easier to give the ball to both backs who are split. How many football plays are designed for or can be designed for the fullback in the I? Very few.

33
by Joe T. (not verified) :: Sun, 04/12/2009 - 10:42pm

Very thorough - good job.

I think something that would be worth investigating is whether this sudden decline among workhorse backs has accompanied a decline in fullback usage, which I suspect, and if there is a relationship, its exact correlation. Looking at your list of 90's era workhorses, I can rattle off the names of some of their fullbacks - Neal, Johnston, Strong, Sellers.

I seem to remember quite a few teams having difficulty lately finding quality fullbacks to fit their offenses, SF, Philly, SD come to mind. I'm wondering whether the shortage of every-down fullbacks is contributing to this apparent decrease in workhorse back usage.

36
by Chris (not verified) :: Tue, 04/14/2009 - 11:06am

Good points doubleb

The last team that I remember that ran a lot of "pro" formations was Seattle (GB used to a lot back in the day with Levens). Now teams run more I, single, and even shotgun next to the QB and much less (pro) formations.

JoeT- Another good point as well. What if the HB and FB are playing the same, it's just additional carries are going to the HB and less to the FB?

37
by Bright Blue Shorts :: Tue, 04/14/2009 - 4:12pm

Ok ... one key thought ... one of the metrics used is 'carries per game' ... understandable because of the 12/14/16 game regular seasons ... but what doesn't seem to have been taken into account is how the NFL has tinkered with the playclock to make games quicker but in the process affecting the number of offensive plays.

Looking at the NFL website teams average 990 plays each which becomes an average of 120 plays per game. And I found this in a 1993 NY Times article ... "Last season games averaged 145.4 plays per game, down from a high of 160.8 plays in the 1987 season."

38
by mrh :: Thu, 04/16/2009 - 9:24am

It's a good point about the varying number of plays per game. That would affect the % of plays that are rushing vs passing. However, the first chart shows that the number of rushes by RBs has been relatively constant since 1987 after peaking in the late '70s. So the workload - rushing at least - being divided up among RBShas been about the same.

Their % share of the total offensive plays may have changed. That is an interesting question that I can't answer right now.