Is Harris one of the league's top cover corners, or a product of the system in which he plays? Cian Fahey says the answer lies somewhere in the middle.
19 Apr 2010
Guest Column by Nate Forster
Just as the names Dwight Freeney and DeMarcus Ware strike fear into the hearts of opposing quarterbacks, the names Vernon Gholston, Erik Flowers, and Jamal Reynolds strike fear into the hearts of general managers. All three of those players were hailed for their raw physical talent and ability to sack college quarterbacks. All three have been NFL flops. When general manages swing and miss on high-end pass rushers, failure looks particularly bad on the stat sheet. Flowers only recorded five sacks over the course of his career, Reynolds only recorded three, and so far, Gholston has exactly zero sacks. Yet, in the same years that Flowers and Reynolds were selected by soon-to-be disappointed teams, savvy clubs snatched up players like Aaron Schobel and Kabeer Gbaja-Biamila later in the draft. Is there a way for teams to know before the draft that players such as Schobel, Gbaja-Biamila, Ware, and Freeney will succeed while players such as Gholston, Flowers, and Reynolds will fall flat?
I have poured through college statistics, biographies, and pre-draft workout data to try and shed light on what is one of the great mysteries of the NFL Draft. The result is SackSEER, a regression model that projects the professional sack totals of college edge rushers selected in the NFL Draft. Edge rusher is defined as a player who has spent a significant part of his career lining up as either a defensive end in a 4-3 alignment or an outside linebacker in a 3-4 alignment. The research to produce the method considered all edge rushers drafted in the first two rounds of the NFL Draft between 1999 and 2008.
There are four main factors that correlate to sack success in the NFL: vertical leap, short shuttle time, sacks per game in college (with some playing time adjustments), and how many eligible games worth of NCAA football the player missed for any reason (except early entry into the NFL Draft). SackSEER projects each prospect's total sacks through five years, which is roughly the average length of the rookie contract received by a first- or second-round pick. Although the individual trends are small, when considered together, they project sack production approximately three times more accurately than a player's draft position within the first two rounds. Overall, SackSEER accounts for approximately 40 percent of the historical variation among these players' accumulated five-year sack totals.
Like Playmaker Score, SackSEER is more accurate at identifying busts than it is at singling out potential stars. The best SackSEER projections include some of the most productive edge rushers in the NFL, but they also include some disappointing players such as Jason Babin and Bryan Thomas. By contrast, if many of the players in the worst SackSEER projections seem unfamiliar, nobody could fault you. With the exception of Tony Bryant, none of the players with the worst SackSEER projections have more than five career NFL sacks.
In the tables below, players with less than five years experience are listed with projected five-year totals based on draft position and sacks so far. These estimates are marked with asterisks.
|Best SackSEER Projections, 1999-2009|
|Aaron Schobel||Texas Christian||2001||BUF||46||40.1||46.5|
|Mario Williams||N.C. State||2007||HOU||1||38.6||39.5 (48.5*)|
|Connor Barwin||Cincinnati||2009||HOU||45||36.5||4.5 (25.5*)|
|DeMarcus Ware||Troy State||2005||DAL||11||35.8||64.5|
|Terrell Suggs||Arizona State||2003||BAL||10||35.3||45.0|
|Courtney Brown||Penn State||2000||CLE||1||34.8||17.0|
|Jason Babin||Western Michigan||2004||HOU||27||34.2||15.0|
|Manny Lawson||N.C. State||2006||SF||22||34.2||12.0 (16.0*)|
|Julius Peppers||North Carolina||2002||CAR||2||33.6||53.5|
|Worst SackSEER Projections, 1999-2009|
|Erik Flowers||Arizona State||2000||BUF||26||10.9||5.0|
|David Veikune||Utah||2009||CLE||52||10.9||0.0 (12.0*)|
|Ikaika Alama-Francis||Hawaii||2007||DET||58||10.9||1.0 (7.0*)|
|Robert Ayers||Tennessee||2009||DEN||18||9.4||0.0 (12.0*)|
|Tony Bryant||Florida State||1999||OAK||40||8.2||17.5|
|Jarvis Moss||Florida||2007||DEN||17||7.6||3.5 (10.5*)|
The trends that SackSEER identifies for edge rushers drafted in the first two rounds persist with later-round edge rushers. For instance, SackSEER would have identified Robert Mathis and Adalius Thomas as top edge rushers. Unsurprisingly, however, SackSEER is not quite as accurate when projecting the edge rusher taken deep in the draft. For now, we are only using the system for players selected in the first two rounds of the NFL Draft. (This will be further discussed in Football Outsiders Almanac 2010.)
Let's look at the four elements in SackSEER and why they help indicate a player's ability to successfully rush the passer in the NFL:
The vertical leap's importance is based on simple physics. If a 270-pound defensive end has the leg strength to jump 40 inches in the air from a standing position, it is very likely that he will be able to employ that same functional strength to burst quickly and powerfully off the line of scrimmage.
The short shuttle run measures change of direction speed, burst, and hip flexibility. DeMarcus Ware had a jaw-dropping 4.07 second short shuttle, and Jevon Kearse ran the short shuttle twice with an average time of 4.12 seconds. No elite edge rusher has emerged from any round of the NFL Draft since at least 1999 with a short shuttle slower than 4.42 seconds.
The third variable in SackSEER is a metric called SRAM, which stands for "Sack Rate as Modified." This measures sacks per game with a few important adjustments. First, sack rates are adjusted to compensate for the fact that college edge rushers as a whole become more productive as they progress through their college careers. A three-year starter who comes out as a junior will be a better prospect than a three-year starter with the same sack rate who is coming out after his senior year. SRAM also attempts to fill in the gaps for players who spent part of their college careers at positions that are less conducive to pass-rushing success, such as defensive tackle (Tamba Hali), 4-3 linebacker (Clay Matthews), or tight end (Ebenezer Ekuban).
The final metric is both the strongest factor and the least intuitive: missed games worth of NCAA eligibility. SackSEER suggests that a college edge rusher who misses numerous games for any reason other than early declaration for the NFL Draft has little chance of succeeding as a professional. This includes players who miss games due to injury, suspensions, academic standards, or sickness. Medical redshirts are included, although standard freshman redshirts are not. Players with health issues in college tend to have health issues in the NFL (Erasmus James, for example). Missing games for other reasons is also indicative of failure at the NFL level. Scroll down to the comment on Jason Pierre-Paul for the remarkable list of failed prospects who spent time at junior college.
The research behind SackSEER will be discussed in more detail in Football Outsiders Almanac 2010, as will the specifics behind the adjustments to sack rate that create SRAM. For now, we wanted to preview this year's draft with a look at how SackSEER evaluates the top edge rusher prospects of 2010. (Please note that the exact projections listed here may differ from those listed in FOA 2010 because of future refinements to the system.)
Vertical: 34.5", Short Shuttle: 4.15, SRAM: 0.55, Missed Games: 3
Projection: 27.7 Sacks through Year 5
Jerry Hughes separates himself from the rest of the pack by virtue of his elite 4.15-second short shuttle run at the Combine. Not only is Hughes' short shuttle time the best amongst defensive linemen in 2010, but it is also better than any shuttle time run by any edge rusher at the Combine in 2009 or 2008.
The other interesting factor with Hughes is a huge jump in SRAM between his sophomore and junior seasons. Hughes recorded only a 0.09 SRAM for his first two years but recorded a 1.0 SRAM during his dominant junior and senior years. This type of improvement compares favorably to other top edge rushers of past drafts. Patrick Kerney, Elvis Dumervil, and Dwight Freeney had 1.0, 2.0., and 3.5 sacks in their first two years, respectively, but subsequently exploded once they became full-time starters in their junior and senior years. Hughes' career path is similar. He was stuck for two years behind Chase Ortiz and Tommy Blake at TCU.
However, Hughes also bears a certain similarity to another prospect who was not quite as successful as Freeney and company: Jason Babin. Babin, like Hughes, recorded a lot of sacks once becoming a full-time starter at a small school, registered a lightning quick shuttle at the Combine and a mediocre vertical leap. Babin, along with Bryan Thomas, is the type of prospect that SackSEER occasionally misses on: a quick, productive, small-school edge rusher who lacks elite explosion. On the other hand, there are plenty of success stories who share Hughes' particular profile, such as Terrell Suggs, Robert Mathis, and Jared Allen. It all adds up to Hughes being a good, but not great, edge rusher prospect.
Vertical: 34", Short Shuttle: 4.43, SRAM: 0.59, Missed Games: 1
Projection: 23.3 Sacks through Year 5
As a prospect, Derrick Morgan is the polar opposite of former teammate Michael Johnson (now with Cincinnati). Morgan was much more productive in college -- building off of a solid sophomore campaign by recording 12.5 sacks in 13 games as a junior -- but lacks Johnson's athleticism, registering mediocre vertical and short shuttle numbers at the Combine. Conventional wisdom says that Morgan is the "safest" edge rusher in the draft, but SackSEER considers Morgan as a middle-of-the-road talent, basically a 50-50 shot.
Vertical: 34", Short Shuttle: 4.36, SRAM: 0.52, Missed Games: 3
Projection: 22.8 Sacks through Year 5
Very few followers of the NFL Draft are particularly excited about Everson Griffen. Unlike Hughes, Griffen has never had a "breakout" season. He has never recorded fewer than 4.5 sacks and never more than eight. Although Griffen's year-to-year sack numbers have been bizarrely consistent at USC, he suffered from consistency problems from game to game, and he was benched more than once for poor play. Giffen's benching only led to him missing three games, so SackSEER is at least lukewarm on his prospects for transitioning to the next level.
Vertical: 31.5", Short Shuttle: 4.25, SRAM: 0.62, Missed Games: 4
Projection: 22.1 Sacks through Year 5
The comparison between Brandon Graham and fellow Michigan alum LaMarr Woodley has been beaten to death by pundits. SackSEER, however, distinguishes Woodley and Graham both by virtue of their prospects for success and by their athleticism. Woodley was an extremely explosive but somewhat "stiff" prospect, recording an excellent 38.5-inch vertical leap and a below-average short shuttle at 4.42 seconds, which added up to a solid 28.2 sack SackSEER projection. Graham, on the other hand, demonstrates good quickness with his 4.25-second short shuttle time, but his 31.5-inch vertical leap raises a major red flag. A more apt comparison for Graham would be Tamba Hali, who shared both Graham’s hustle and lack of jumping ability coming out of college.
Vertical: 36.5", Short Shuttle: 4.53, SRAM: 0.48, Missed Games: 7
Projection: 18.8 Sacks through Year 5
Kindle had a standout performance with two sacks in the National Championship game against Alabama. Very few people have noticed that Kindle had only four sacks in the Longhorns' other 13 games.
Kindle played linebacker for his first two years at Texas, so he gets the full benefit of SRAM's adjustment for playing "out of position." That experience leads many to believe that Kindle is an ideal fit as a 3-4 outside linebacker, but SackSEER is markedly apprehensive due to Kindle's relatively low productivity and missed games. Kindle has suffered multiple minor knee and ankle injuries and, although it is not as fresh in the minds of the football-loving public as Dunlap's DUI, Kindle also served a three-game suspension because of a drunk driving incident.
Kindle's good 36.5-inch vertical leap improves his projection somewhat, but it is more or less canceled out by his poor shuttle run. The most successful edge rushers drafted between 1999 and 2008 after running a 4.5-second shuttle or slower in were Ray Edwards and Tony Bryant. These players had their best seasons as strong-side defensive ends in a 4-3, often lining up opposite slower-footed right tackles. As a classic 'tweener, whose size limits him to rushing the passer and dropping back in coverage, Kindle will probably not be able to fill a similar role.
Vertical: 31.5", Short Shuttle: 4.61, SRAM: 0.62, Missed Games: 2
Projection: 16.1 Sacks through Year 5
Carlos Dunlap may be a victim of his own hype. At Florida, Dunlap was billed as the next in the line of big men -- such as Mario Williams and Julius Peppers -- with the rare combination of size to be stout against the run and speed to rush the passer. However, many who have reviewed Dunlap's game tape have accused him of "taking plays off" and "not playing as fast as he times."
These critics may be half right, because Combine numbers suggest that Dunlap's total athleticism doesn't match his raw straight-line speed. Compare Dunlap's 31.5-inch vertical leap to those of Mario Williams and Julius Peppers, who leapt 40.5 inches and 36.5 inches, respectively. Dunlap's vertical leap is far more similar to those of the unsuccessful Florida Gators of recent past -- Derrick Harvey and Jarvis Moss. Dunlap also failed to impress with his short shuttle. Ironically, Dunlap's redeeming characteristic is his productivity on the field, where he has received the most criticism.
Vertical: 30.5", Short Shuttle: 4.67, SRAM: 0.44, Missed Games: 26
Projection: 3.8 Sacks through Year 5
This projection is not a misprint. Although Pierre-Paul is widely regarded as one of the top edge rushers by draftniks, it is hard to conceive of a prospect that SackSEER would like less.
Is it fair to say that Pierre-Paul 26 missed games because he spent his first two years in junior college? Yes, because the few recent edge rusher prospects with junior college experience were among the worst defensive draft picks in recent memory. The illustrious list includes Anton Palepoi, Jerome McDougle, Tony Bryant, Lamar King, Erik Flowers, Michael Boireau and most recently, David Veikune, Cleveland's 2009 second-round pick, who did not record a sack as a rookie and was inactive for much of the season. Unless you count Julian Peterson, a 4-3 linebacker who doesn't fit this study, you have to go back to Leonard Little in 1998 to find a former junior college player who panned out in the NFL, and Little spent only one year at junior college. When Tony Bryant is your upside, you're in trouble.
So why do junior college edge rushers struggle so mightily when transitioning to the NFL? Most edge rusher prospects who play at the junior college level miss two years worth of their NCAA eligibility, and they are understandably "raw" when they enter the professional ranks. Although many coaches believe that such a player can be "coached up," the coaching staff can only devote so much of its valuable coaching resources to a single player. Moreover, many players who go to a junior college have significant or severe academic issues, and expecting them to digest a complicated NFL playbook while also "catching up" on their fundamentals may be unrealistic.
However, even if we removed the missed games adjustment, Pierre-Paul would still have the worst projection in this class. Although Pierre-Paul's "handflips" video has earned him the distinction as the 2010 NFL Draft's consummate physical "freak," he put up poor numbers in all of the workout metrics that matter to SackSEER. This is certainly not the first time that similar "gimmicky" athleticism has not translated into workout numbers. For instance, just last year, San Diego State defensive lineman Jarron Gilbert made waves (pardon the pun) with a widely circulated video depicting Gilbert jumping out of a swimming pool flat footed. Despite his aquatic jumping ability, Gilbert only registered a 35.5-inch vertical leap at the Combine.
The ability of Pierre-Paul to translate his particular brand of athleticism to pass rushing success is speculative at best. Overall, the general manager who pulls the trigger on Pierre-Paul better be very confident that he has something special -- so special that it will completely buck the historical trends.
When it comes to sleepers, SackSEER rates two prospects above the rest: South Carolina linebacker Eric Norwood and Washington defensive end Daniel Te'O'Nesheim. Eric Norwood's Combine numbers are similar to those of Clay Matthews a year ago, and he had better college sack production. Te'O'Nesheim has been billed as a productive, high-energy player who lacks the athleticism to compete at a high level, but his 37-inch vertical leap and a 4.18-second short shuttle at the Combine are enough to convince SackSEER.
Nate Forster is an attorney in Boston whose hobbies include drinking Slurpees, wearing hooded sweatshirts, and delivering bone-crushing hits on opposing quarterbacks. Although never invited to the NFL Combine, he did hold a personal pro day where he amazed all in attendance by reading a transcript of a Todd McShay-Mel Kiper debate in the voices of Shaggy and Scooby Doo. Special thanks to my fiancée for putting up with me while I "was doing stats," and to the posters at the FootballOutsiders.com forums, especially AlanSP, for their thoughtful comments on an early version of this model.
Editor's Note: If you are interested in publishing a guest column at Football Outsiders, please e-mail your idea or rough draft to info-at-footballoutsiders.com. Come up with something really good, like SackSEER or the Lewin Career Forecast, and we may even ask to publish it in our book.
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