Neil’s NFL Daily: May 29, 2013

After offering thoughts on BJ Raji's contract situation, Neil Hornsby continues exploring subset scouting pitfalls and player consistency with a focus on cornerbacks.

| 4 years ago

Neil’s NFL Daily: May 29, 2013

As the news came in yesterday, the item that made me think the most was related to B.J. Raji’s contract. With 2013 being the last year of his deal, will the Packers extend? And if so, what is fair remuneration? The problem for Green Bay is that there have been few more inconsistent players on a year-to-year basis than Raji. His -4.8 grade on 40% of snaps his rookie year was understandable, particularly as he built brilliantly on that in 2010 earning a +15.1 grade while playing 85% of snaps and showing real ability as a pass rusher — his Pass Rushing Productivity in all games, including the playoffs, of 6.6 ranking him fifth among interior linemen.

However, in 2011, on 79% of snaps, not only did that number drop dramatically to 3.4 (now ranking him t25th of 32 qualifiers) but his run defense degenerated to the genuinely awful (ranked dead last). Last year, although he didn’t reach the heights of 2010, he did improve and for the first time in his career graded positively in both pass rush and run defense. And there’s the front office’s problem — which B.J.Raji are the paying for? At his very best he may be worth $9m a year, but at his worst $2m would be the equivalent of going to the top of a tall building and throwing the cash to the winds.

On the subject of inconsistency, yesterday we started a series about the variation in game-by-game player performance during the 2012 season. We looked first at the wide receivers so now let’s turn our attention to the men covering them — cornerbacks.


Wednesday, May 29th

Subset Scouting

I explained the concept in some detail yesterday, so if you didn’t catch the principle it’s all here.

In essence, we are examining which players show the most variation in performance and who are the least likely to tease you with a great game the one day you tune in and then stink it up while you are off watching other players the following week.


The table below shows the overall grade, together with those for the player’s best four games and worst four.


Top 20 Cornerbacks Ranked by Grade Differential

RankNameTeamOverall GradeSum Best Four GradesSum Worst Four GradesBest/Worst Difference
1Tramon WilliamsGB-0.212.1-14.326.4
2Sheldon BrownCLV7.913.8-11.225.0
3Dunta RobinsonATL2.511.8-11.923.7
4Jabari GreerNO-0.412.2-11.623.8
5Michael HuffOAK2.313.5-11.424.9
6DeAngelo HallWAS-3.210.6-13.924.5
7Cary WilliamsBLT-3.210.0-14.124.1
8Dominique Rodgers-CromartiePHI-7.111.0-11.022.0
9Brandon CarrDAL0.111.0-10.521.5
10Buster SkrineCLV-3.98.7-13.121.8
11Janoris JenkinsSL-7.98.2-14.923.1
12Nnamdi AsomughaPHI-8.08.3-12.220.5
13William GayARZ-9.98.1-11.819.9
14Josh WilsonWAS3.69.3-9.518.8
15Carlos RogersSF3.910.2-8.718.9
16Morris ClaiborneDAL-4.57.8-11.519.3
17Cortland FinneganSL-5.69.0-9.818.8
18Chris CulliverSF1.211.2-7.718.9
19Alterraun VernerTEN7.115.0-7.022.0
20Captain MunnerlynCAR0.49.6-9.018.6

Unlike the receivers yesterday, which featured a fairly high percentage of true “upper echelon” players, this group does read much more like a cross-section of those that flatter to deceive. Not a single one of these players came close to our All-Pro team, although many did get praise well beyond their performance. Interceptions, being the only thing some of the lazier commentators focus on, meant guys like Janoris Jenkins (although he did reasonably for a full-time rookie corner) garnered significantly more kudos than they deserved. Some even talked about him as Defensive Rookie of the Year, which is frankly absurd.

Not surprisingly, DeAngelo Hall, the man who in 2010 infamously gained Pro Bowl recognition on the back of one four-interception game despite giving up the second largest amount of yards in the league and a 105.8 QB rating into his coverage that year, is still showing much of his hit-or-miss style of play.


CB Consistency Counts

Now a look at the 10 most consistent cornerbacks. Once again these are ranked by the standard deviation of coverage grades.


Corners Ranked by Consistency of Grades (minimum 500 snaps)

RankNameTeamSnapsOverall GradeSD
1Devin McCourtyNE53412.70.9
2Jimmy WilsonMIA605-7.41.02
3Josh RobinsonMIN651-10.31.07
4Josh ThomasCAR530-1.71.08
5Stephon GilmoreBUF1082-4.31.13
6Robert McClainATL61310.61.13
7Marcus GilchristSD640-5.21.15
8Brandon FlowersKC88213.71.15
9Josh NormanCAR788-6.91.16
10Kyle ArringtonNE8442.41.19

This is very much a mixed bag. It’s a combination of players who were consistently very good (Devin McCourty, Robert McClain and Brandon Flowers), consistently poor like Josh Robinson (although never terribly disastrous), or the remarkably average.

McCourty deserves special mention as this performance came across two positions, as he played both corner and safety to an incredibly high standard. He never graded below -0.5 in coverage and never above +2.1. His week-by-week grades are the very model of what is expected of a player in the secondary, but my betting is his lack of highlight plays means he doesn’t get close to the recognition his play warrants.


Follow Neil on Twitter: @PFF_Neil


| PFF Founder

Neil founded PFF in 2006 and is currently responsible for the service to the company's 22 NFL team customers. He is constantly developing new insights into the game and player performance.

  • BrennenWarner

    I calculated Adam Jones’ standard deviation to be 1.07, putting him in a tie for third best. What did you guys have?

  • BrennenWarner

    Also, Neil, are you planning a consistency article on safeties? If not, did the top ten safeties generally have lower standard deviations than the corners?