2011 Formation Analysis: Number of RBs Part II

2011 Formation Analysis: Number of RBs Part II
2011 Formation Analysis: Number of RBs Part II
Photo: USA Today Sports Images

by Rivers McCown

Continuing our look at game-charting statistics from the 2011 season that'll be featured in Football Outsiders Almanac 2012, this time we'll examine the tendencies and performances of run defenses based on the number of running backs they faced. (We did offenses two weeks ago.)

The big difference between the offensive stats and the defensive stats against multiple-back sets is the lack of definitive conclusions to be drawn from them.

Take last season. The three teams that saw the most multiple-back sets used against them were St. Louis, Indianapolis, and Cleveland. Simple narrative, right? Bad teams faced more multiple-back sets as teams tried to run the clock out against them. A little over halfway through the season, we ran a chart about the teams that spent the most game time in the lead, and those three teams spent the most time trailing. The only other teams that saw multiple-back sets 55 percent or more of the time, Seattle and Carolina, were also losing teams.

However, go back to 2010, and you'll find the teams that faced the most multiple-back sets were New Orleans, Seattle, and Cleveland. That's a pair of playoff teams, though one of them of course had a losing record in the regular season. The interesting thing is that St. Louis and Indianapolis finish above 60 percent again in 2010, along with a couple of teams you probably wouldn't expect in Atlanta and Philadelphia. On a per-play statistical basis, there doesn't seem to be much reason to target those teams heavily. Nor is there much precedent for this as a purely divisional thing -- if it were, we'd expect to see Tennessee in the mix because of Houston and Baltimore, and we wouldn't expect to see St. Louis at all since Seattle and Arizona haven't shown much of a bias and the 49ers only truly embraced multiple-back sets last season. My anecdotal guess would be that it has to do with perceived personnel weaknesses at linebacker. Most of these teams have had a solid man in the middle (D'Qwell Jackson, James Laurinaitis, Jonathan Vilma, Gary Brackett), but the outside positions have been in flux for the past few seasons.

It certainly appeared that offenses were targeting these teams smartly, as four of the five teams that saw the most multiple-back sets in 2011 saw a decline in DVOA when facing them. Seattle actually was almost 15 percent better against multiple-back sets. However, they were slightly worse against it (~4 percent) in 2010. Perhaps old information was relied on?

The Eagles, weak linebackers and all, were the worst team in the league against single-back sets. That shouldn't be a surprise to their fans and they'll move forward with DeMeco Ryans and Mychal Kendricks hoping they've addressed that problem. The second-worst team against single-back sets, Tennessee, dealt with some rookie mistakes from Akeem Ayers and a half-season of a turnstile middle linebacker in Barrett Ruud. A full season of Colin McCarthy should help remedy half of that problem. The funny thing is that both Philadelphia and Tennessee were both much better against multiple-back sets. In fact, last year no team improved their run defense as much as those two did with multiple-back sets on the field. Perhaps that says something about the value of having an every-down linebacker who can tackle?

The teams that saw the fewest multiple-back sets also tend to clump together a bit. In 2011, the teams that saw under 40 percent of runs against them come from multiple-back sets included Dallas, Miami, Kansas City, and Oakland. In 2010? Miami was the only one, but if we scale back a little bit to hit 45 percent, we find Washington, Kansas City, New England, the Jets, and Baltimore. Again, this seems to tie into a trend we pointed out in our play-action defense post: the 3-4 defense. Every one of those teams besides Oakland is at least a hybrid defense, if not a pure 3-4.

Below are all the running statistics we keep for single- and multi-back formations, sorted by the difference in DVOA allowed between single-back and multi-back sets. This is about formation, not personnel: if a receiver is in the backfield, for the purposes of this study, he is counted as a back. Also, no Wildcat-style runs were counted, meaning we did not include (among a few other rare things) direct snaps to running backs or receivers.

2011 Rushing Defense by Number of Backs
Defense DVOA vs.
1 RB
DVOA vs.
1 RB Pct. 2+RB Pct.
TEN 6.1% -25.3% 31.3% 50% 50%
PHI 6.3% -15.6% 21.9% 52% 48%
DET -4.1% -25.6% 21.5% 49% 51%
DEN -4.1% -23.7% 19.5% 53% 47%
CHI -19.1% -35.6% 16.5% 53% 47%
ATL -14.8% -30.5% 15.6% 60% 40%
KC -4.0% -18.9% 14.9% 67% 33%
NO 4.3% -10.0% 14.3% 47% 53%
SEA -5.1% -19.4% 14.3% 45% 55%
DAL -9.4% -22.4% 13.0% 68% 32%
SF -25.0% -35.0% 10.1% 52% 48%
Defense DVOA vs.
1 RB
DVOA vs.
1 RB Pct. 2+RB Pct.
PIT -4.0% -13.6% 9.6% 51% 49%
GB 4.2% -4.2% 8.4% 56% 44%
CIN -2.3% -10.2% 7.9% 48% 52%
JAC -16.0% -23.7% 7.8% 56% 44%
HOU -16.0% -23.4% 7.4% 47% 53%
ARI 1.5% -5.4% 6.9% 54% 46%
BAL -14.6% -21.1% 6.5% 58% 42%
WAS -12.1% -16.2% 4.1% 49% 51%
NE 1.0% -1.3% 2.4% 58% 42%
NYJ -22.7% -23.5% 0.8% 55% 45%
BUF 3.0% 3.9% -1.0% 47% 53%
Defense DVOA vs.
1 RB
DVOA vs.
1 RB Pct. 2+RB Pct.
MIA -15.6% -11.1% -4.5% 65% 35%
IND -7.1% -1.0% -6.1% 40% 60%
OAK -0.9% 5.5% -6.4% 61% 39%
CLE -2.5% 4.7% -7.2% 43% 58%
CAR 5.6% 13.8% -8.3% 45% 55%
SD -7.6% 2.4% -10.0% 58% 42%
STL -6.5% 3.6% -10.1% 40% 60%
TB -0.3% 10.2% -10.5% 51% 49%
MIN -20.4% -8.3% -12.1% 47% 53%
NYG -18.0% 5.8% -23.9% 59% 41%
NFL -6.8% -10.4% 4.8% 53% 47%


6 comments, Last at 16 Jul 2012, 12:26pm

1 Re: 2011 Form. Analysis: Number of RBs Part II

For the most part, there's not much noteworthy in these tables, except for the cases of the Giants and the Seahawks. Curiously, opponents tended to run out of sets that those two defenses were significantly more effective against (1-RB sets for the Giants and 2-RB sets for SEA). One wonders how they managed to fool opponents into playing into their defensive strengths.

2 Re: 2011 Form. Analysis: Number of RBs Part II

To my eyes, I think the Eagles table suggests something that a lot of fans saw: the organization knew it had bad LB's and good CB's, so it was very quick to get all 3 of Asomugha, Samuel and DRC on the field at the same time - basically it looks like they would drop into a nickel anytime there was only a single back lined up. Then, you could run on them with ease. It hurt them that not one of their 3 CB's could tackle worth a good goddamn. Additionally, their LB's were generally confused/lost in coverage and not able to account for the run if they had more obvious coverage duties to consider.

With 2 RB's in the backfield, though, they suddenly became pretty darn good against the run - more likely to have all 3 LB's on the field and with much simpler coverage responsibilities. Hence, the huge difference in DVOA between their 2 packages.

3 Re: 2011 Form. Analysis: Number of RBs Part II

And sometimes it comes down to a single player. For the Lions, LB Justin Durant is excellent against the run but a liability against the pass, so he's not on the field for likely passing situations. That probably explains the big difference in DVOA for the Lions.

My comment regarding the Seahawks and Giants was to point out that their opponents tended to run packages that played into their run D strengths more than anyone else. It's as if opponents couldn't tell that the Giants played worse against 2-back sets than against single-back sets. Just seemed weird, unless opponents simply had no respect for the Giants secondary.

4 Re: 2011 Form. Analysis: Number of RBs Part II

Well, the Giants' trajectory last year is so crazy it's hard to speculate what any of their numbers mean. I think from my own viewing experience, teams (rightfully) wanted to target their utterly-incompetent-in-coverage LB's with an underneath attack and having 2 RB's on the field was an effective method. They wanted as many LB's on the field as possible. This meant, though, that their strength (their run d) would get a chance to shine if you actually tried to run the ball (which you sorta need to do occasionally to keep them honest.)