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16 Mar 2011

Best Cornerback Charting Stats 2010

by Aaron Schatz

The offseason is usually a slow time around Football Outsiders, but this offseason is particularly slow since we don't have any free agency to discuss (or free agent signing news stories to link to in Extra Points). Let's see if we can fill the next few weeks with some of the many numbers that we've collected over the course of the 2010 season.

One thing we haven't yet done this year is look at the full game charting numbers for cornerbacks in 2010. These tables rank all cornerbacks with at least 40 charted passes. (Interestingly, the number of cornerbacks who hit this minimum has gone up from 70 in 2009 to 83 in 2010.) I've removed passes marked as Hail Mary, Hit in Motion, Tipped at Line, or Thrown Away. I've also removed wide receiver screens, which aren't really a good way to measure cornerback coverage because a cornerback in man coverage is going to (or at least, is supposed to) immediately get blocked out of the play by another wide receiver. Right now I'm only looking at primary defenders, so this is not adjusted to account for double coverage, or plays where the charter marks a hole in zone but lists an appropriate zone defender in the second DEFENDER column. There are no opponent adjustments yet, and pass interference is not yet included.

Typical caveats apply, of course: This is imperfect data based on the game charting project, which means it comes off limited television camera angles. In past years, this data has been very inconsistent from year to year, and we're going to study that in the offseason to try to figure out if we can get more accurate numbers by, say, looking at players over two-year spans. (I wrote this last year as well, but this offseason we have, shall we say, "extra free time.")

Success Rate, to remind everyone, is the percentage of passes that don't manage to get at least 45 percent of needed yards on first down, 60 percent of needed yards on second down, or 100 percent of needed yards on third down.

Top 10 Cornerbacks in Success Rate, 2010
Player Team Charted
Targets
Yd/Pass Rk Success
Rate
Rk Avg. Pass
Distance
YAC Rk
Darrelle Revis NYJ 57 5.6 11 70% 1 16.5 4.7 74
Antoine Winfield MIN 57 4.2 1 67% 2 9.0 3.4 40
Stanford Routt OAK 92 5.7 13 66% 3 15.1 4.9 77
Tramon Williams GB 83 5.5 9 66% 4 14.3 4.0 55
Ronald Bartell STL 83 5.2 5 65% 5 14.0 3.2 36
Sean Smith MIA 49 6.7 29 63% 6 11.8 4.4 68
E.J. Biggers TB 65 5.7 12 63% 7 13.3 2.9 25
Joselio Hanson PHI 46 4.4 2 63% 8 9.2 1.5 1
Antonio Cromartie NYJ 102 6.0 16 63% 9 17.1 3.2 32
Brandon Carr KC 105 7.1 35 61% 10 16.1 4.2 58

This just in: Darrelle Revis continues to be awesome, recovering nicely from the hamstring issues he had early in the season. Antoine Winfield is also playing at a very high level despite being in his mid-30's, although his metrics are exceedingly strong in part because the mostly Cover-2 defense they play in Minnesota keeps him away from covering long passes. I discussed Stanford Routt's shockingly good numbers back when he signed his new contract a couple weeks ago. If you are surprised to see Brandon Carr on this top ten list rather than Brandon Flowers, I can tell you that Flowers ranked 12th in Success Rate. However, go read the AFC Wild Card game preview and scroll down halfway to a discussion of how Flowers' value was dramatically higher in the first three weeks of the season, and he didn't necessarily have the overall improvement that conventional wisdom says he had last year.

Interesting to note that the top cornerbacks in Success Rate are almost all near average or below when it comes to average YAC allowed. However, as you will see two tables down from here, the cornerbacks ranked 11th through 13th in Success Rate were all in the top 10 for fewest YAC allowed, so I don't know if this is truly meaningful.

Top 10 Cornerbacks in Yards per Pass, 2010
Player Team Charted
Targets
Yd/Pass Rk Success
Rate
Rk Avg. Pass
Distance
YAC Rk
Antoine Winfield MIN 57 4.2 1 67% 2 9.0 3.4 40
Joselio Hanson PHI 46 4.4 2 63% 8 9.2 1.5 1
Justin Tryon IND 42 5.0 3 60% 13 10.5 2.2 6
Brent Grimes ATL 111 5.0 4 60% 11 13.0 2.0 5
Ronald Bartell STL 83 5.2 5 65% 5 14.0 3.2 36
Javier Arenas KC 51 5.4 6 45% 69 8.3 2.6 14
Jason McCourty TEN 42 5.5 7 55% 30 11.1 3.2 35
Ronde Barber TB 49 5.5 8 53% 37 9.1 3.4 43
Tramon Williams GB 83 5.5 9 66% 4 14.3 4.0 55
Jerraud Powers IND 59 5.6 10 56% 24 11.7 2.8 23

In my opinion, the strangest name on these lists is Ron Bartell. Highly-drafted cornerbacks often take three or four years to develop, but Bartell was a second-round pick in 2005, so this was year six. We'll have to wait a year to see whether Bartell's improvement sticks, as there's a history of veteran cornerbacks randomly having excellent years. (Drayton Florence was near the top of these lists in 2009.) Do you like Javier Arenas' numbers? Yes, he was covering short-route slot receivers this year.

Top 10 Cornerbacks in YAC Allowed, 2010
Player Team Charted
Targets
Yd/Pass Rk Success
Rate
Rk Avg. Pass
Distance
YAC Rk
Joselio Hanson PHI 46 4.4 2 63% 8 9.2 1.5 1
Champ Bailey DEN 65 7.6 48 54% 35 14.7 1.7 2
Captain Munnerlyn CAR 61 6.6 27 56% 26 12.9 1.9 3
Brandon Flowers KC 97 6.3 18 60% 12 14.7 2.0 4
Brent Grimes ATL 111 5.0 4 60% 11 13.0 2.0 5
Justin Tryon IND 42 5.0 3 60% 13 10.5 2.2 6
Bradley Fletcher STL 76 6.9 33 53% 41 15.8 2.2 7
Lardarius Webb BAL 71 6.3 19 56% 22 15.6 2.2 8
Johnathan Joseph CIN 57 6.8 32 53% 40 11.1 2.3 9
Chris Carr BAL 77 5.9 14 56% 25 9.9 2.4 10

One more tidbit for today. Here are the stats for two top cornerbacks who did not have enough targets to be ranked above:

Player

Charted
Targets
Yd/Pass Success
Rate
Avg. Pass
Distance
YAC
Nnamdi Asomugha 31 5.9 61% 15.4 3.7
Asante Samuel 36 3.2 78% 15.0 1.9

With four more pass targets, Samuel would rank as the top cornerback in both Success Rate and yards per pass. (He will in Football Outsiders Almanac 2011, since our ratings in the book generally waive the minimum for cornerbacks who had at least eight starts.)

Friday, I'll flip the script and run "10 worst" tables for cornerback charting stats.

Posted by: Aaron Schatz on 16 Mar 2011

56 comments, Last at 11 Aug 2011, 12:10pm by Sports-Glory

Comments

1
by MilkmanDanimal :: Wed, 03/16/2011 - 4:39pm

I'd had a vague sense that E.J. Biggers had played pretty well this year, but #7 in success rate? I guess through a fair portion of the season he got to face the #2 or #3 WR, as Aqib Talib was handling #1, but still a bit of a surprise.

55
by MikeM (not verified) :: Mon, 08/01/2011 - 3:45pm

Calvin Johnson had his way with E.J. Biggers, so I would assume that you are correct in saying Biggers had the majority of his success against #2 and #3 receivers.

2
by Joseph :: Wed, 03/16/2011 - 4:40pm

All I can say re: that last chart is "WOW!" 2 targets per game.

Dear Nnamdi:
Do want to come to an organization that recently won a SB, and still has one of the best QB's in football? Do you want to play for a DC who likes to play man while blitzing so the QB has to throw the ball too early? Do you NOT like winter weather? If you answered "yes" to all these questions, please come visit New Orleans as soon as the rules allow. I cannot promise $20MM yearly salary, but I can make a fair offer.

Sincerely,

Tom Benson

3
by battlered90 (not verified) :: Wed, 03/16/2011 - 4:43pm

10 worst cornerbacks or the Houston Texans starting secondary

4
by Flounder :: Wed, 03/16/2011 - 4:44pm

Interesting data. I'm glad to see the subjective impression of Tramon William's awesomeness this year backed up by the stats. Williams being so awesome plus Sam Shields randomly being probably as good Tramon Williams circa 2009 were critical to the success of the GB defense last year.

His YAC ranking is pretty low though. What is the consistency on that state from year to year? I seem to recall one or two plays this year where Tramon gambled and lost, plus one or two crossing patterns where Tramon lost his man/got caught in the scrum and the play went for big yards.

50
by Ryan (not verified) :: Mon, 03/28/2011 - 6:17pm

True his YAC was high-ish, but on first glance, it looks like YAC correlates pretty strongly with yards per target. His is one of the higher ones.

5
by QQ (not verified) :: Wed, 03/16/2011 - 5:19pm

The 85 yard TD that Tramon gave up to Mannigham likely did not help his YD/Pass

37
by Flounder :: Fri, 03/18/2011 - 9:30am

Ahhh, yes, that's exactly one of the plays I was thinking of, it just didn't quite come to mind. I think that was the only TD pass he gave up all year.

6
by bubqr :: Wed, 03/16/2011 - 5:25pm

lol@Joselio Hanson

9
by phillyangst :: Wed, 03/16/2011 - 6:24pm

Don't laugh. Toastelio covers the slot receiver where most of the passing routes are shallow crosses or quick hitches. He was exceptionally good this past season. One of the few highlights of a disappointing Iggles defense.

"DVOA loves Philadelphia!"

32
by Pass to Set Up ... :: Thu, 03/17/2011 - 4:11pm

Yeah, Hanson gets shit, but he's a good nickel corner. Moving him outside to cover a wide receiver running a deep route and he's toast, but he's good at his assigned job.

So if Asante Samuel is great outside, and Hanson is good against the slot, if the Eagles spent a wild amount of money to bring Asomugha to Philly we would have arguably the best secondary in the league.

Then all we'd have to worry about is our dysfunctional linebackers and our d-line that fades down the stretch.

Oh yeah, and a d-coordinator who until recently was an o-line coach...

39
by chemical burn :: Fri, 03/18/2011 - 3:32pm

I knew Asante had great numbers, but seeing Joselio on there really makes this a legit question: was Dmitri Patterson the biggest liability in a defense of all time?

7
by tuluse :: Wed, 03/16/2011 - 5:30pm

Charles Tillman does not make any list, as expected. He usually grades out with very average stats, but a ton of attempts. Which is valuable in it's own way. However, I wonder if we could get a look at largest differences between teammates. Tim Jennings looked a lot worse to me, and I wonder if that showed up in the stats.

8
by Peregrine :: Wed, 03/16/2011 - 5:48pm

Brent Grimes... Grime Time... Five Feet of Fury... Destroyer of Worlds

10
by Anders Jensen (not verified) :: Wed, 03/16/2011 - 6:40pm

I knew Samuel had a good season, but that statline is just insane.

This data also shows that Hanson does his role really well, covering the slot reciever.

I know Nnamdi was injuried this season, but I would be an happy Eagles fan if they sigend him.

17
by phillyangst :: Thu, 03/17/2011 - 10:09am

That stat line for Asante is attributed to the poor play of Ellis Hobbs and Dimitri Patterson. Don't be surprised to see Patterson at the top of the list for "Worst Cornerback Charting Stats 2010". Let's not lessen the importance of quarterback pressure on cornerback performance. Trent Cole cannot do it alone.

"DVOA loves Philadelphia!"

23
by Noah of Arkadia :: Thu, 03/17/2011 - 12:43pm

I don't see how having less effective teammates would make a player more effective! I figure if QBs have a weak link or two to throw against, they will pick their chances better when throwing against the stronger player, making it more difficult for latter on a per target basis.

36
by phillyangst :: Fri, 03/18/2011 - 9:18am

Agreed. Samuel defended passes more effectively than Hobbs and Patterson.

"DVOA loves Philadelphia!"

11
by andrew :: Wed, 03/16/2011 - 8:01pm

I have a feeling Nnamdi might have had more playing time had he not had such an incentive to fail to meet the numbers in his contract...

12
by KJT :: Wed, 03/16/2011 - 8:16pm

I think you guys spelled Asante Samuels wrong

13
by BigDerf :: Wed, 03/16/2011 - 10:24pm

Does game charting mention whether or not there was pressure in the QBs face at the time of the pass? I feel like Cromartie's and possibly Revis' numbers are influenced by the Jets exotic blitzes.

14
by DSG (not verified) :: Thu, 03/17/2011 - 2:40am

Why limit it to cornerbacks targeted 40 times? If a cornerback can completely prevent a QB from throwing to his side of the field, isn't that a good thing? See, e.g., Sanders, Deion and Revis vs. Wayne 1.0 and 2.0.

18
by Aaron Schatz :: Thu, 03/17/2011 - 11:19am

Without minimums, the best and worst lists would be dominated by dime backs and injury replacements.

22
by nat :: Thu, 03/17/2011 - 12:34pm

I think the question is more about why a minimum number of targets rather than a minimum number of plays.

I understand why you chose target count - it's the sample size for the stats. Your limit is not about whether A.S. deserves to be listed, but whether his stats deserve to be trusted.

For me, I would prefer to have a play count minimum, with the target count shown so I can interpret the stats myself.

30
by tuluse :: Thu, 03/17/2011 - 3:54pm

Substitution data would be the holy grail of defensive backfield statistics. Unfortunately, it is virtually impossible to attain.

41
by nat :: Fri, 03/18/2011 - 4:44pm

Ah, I had forgotten that. With charting we get info on who was targeted. It's too much to ask that we also get who else was on the field - charters can only watch so much at a time, and video only shows so much.

My thanks go out to everyone involved in the charting work.

46
by Andy (not verified) :: Mon, 03/21/2011 - 11:46am

Do you mean you'd want snap-counts? (ie: so you could have a minimum snap requirement, then look at targets?)** If so, I think those are definitely doable - even with TV angles. I've never seen FO's pay-data so I don't know if they have these, but I've been to other (free at one time) sites that do. Sure, anyone can argue that it's not accurate but the same can be said for ANY data. And really, it wouldn't be too far off in regards to the high # of snaps in a full season.

**Counterpoint: I know we all want to include Nnamdi & Asante but if we used a snap-count requirement, a lower sample size of targets could still lead to statistical problem (yea, they weren't like under 10 but in some instances this could be the case).

47
by tuluse :: Mon, 03/21/2011 - 5:17pm

those are definitely doable - even with TV angles

Multiple writers for FO have disputed this. Especially in regards to defensive backfield players who are often not on the screen at all during the start of a play, and it's often hard or impossible to read their jersey numbers when they are.

48
by Neoplatonist Bolthead (not verified) :: Mon, 03/21/2011 - 7:33pm

There's some source for snap counts, whether you trust it or not. I know I've seen that data online; if nothing else, Kevin Acee of the San Diego Union Tribune talks about it like he's getting it from somewhere. If you include snap counts as a threshold only, inaccurate data is not that big a deal, so long as it's plausible. The worst likely outcome of including players with at least about 300 snaps is wrongly including or excluding a couple marginal players.

49
by tuluse :: Mon, 03/21/2011 - 10:29pm

Well yes, teams track snap counts, and beat writers can become privy to this information (Brad Biggs does the same thing for the Bears). However, it is not freely available. Also, pro football focus tries to divine the data from TV angles, but several members of FO have challenged that this information is anywhere close to accurate.

33
by RC (not verified) :: Thu, 03/17/2011 - 5:49pm

Theoretically.

Of course, it could just mean that the guy across from him sucks.

15
by dryheat :: Thu, 03/17/2011 - 8:22am

I'm betting that Alphonso Smith makes the worst list based on his game vs. New England alone.

16
by PackerBacker (not verified) :: Thu, 03/17/2011 - 9:46am

Just curious if non-top 10 CB data will be made available. Since the Packers rode a strong secondary to a Super Bowl victory (was really the freedom that Dom Capers enjoyed with three solid corners that allowed the defense to do so well) it might be interesting to see where Woodson and Sam Shields rank.

19
by Aaron Schatz :: Thu, 03/17/2011 - 11:21am

It will be in Football Outsiders Almanac 2011.

20
by Barry (not verified) :: Thu, 03/17/2011 - 11:54am

Interesting to see Justin Tryon to figure highly on the lists. As a colts fan, he did impress me on several occasions throughout the season, but he didn't exactly standout as exceptional. It'll be interesting to see if he can continue above average play, or if last year was his peak and he'll revert to more mediocre performances. Not sure if they signed him to just a one year deal, or if it was longer.

21
by Yesimadolphinsfan (not verified) :: Thu, 03/17/2011 - 12:29pm

I am surprised to see Sean Smith anywhere near any of these lists, as it seemed like last season I spent most of my time screaming at him more than anyone in the Dolphins secondary. Thinking back though, that may have only been because his hands of stone physically can not catch a football.

So I guess he's at least doing something right, that's good.

25
by Independent George :: Thu, 03/17/2011 - 1:26pm

That brings up an interesting question - all other things considered equal, is it better to have a solid corner with hands of stone, or a gambler who gets regular picks by jumping routes, but also gets burned fairly often? I other words, what is the relative value of a turnover vs. chunks of yardage?

I wonder if the answer differs depending on the team - that is, if you've got a decent pass defense, I think I'd rather have a solid player to prevent holes than someone who will give up a lucky score. On the other hand, if nobody else in your secondary can cover, the downside of giving up a big play is minimal compared to the possibility of a turnover.

27
by commissionerleaf :: Thu, 03/17/2011 - 2:25pm

My view is that while the choice of cornerbacks probably depends on the team, a fully game-theoretic perspective would demonstrate that it really doesn't matter; that some minimax of interception potential and coverage discipline is the relevant factor in most cases.

But, as I said, NFL teams don't think that way; Washington's choice of DeAngelo Hall, for instance, makes a lot of sense (from your perspective) given their anemic offense. Likewise Ike Taylor in Pittsburgh. However, this strategic element is probably "lost in the noise" of drive-level effects. It "feels" right, but probably doesn't matter.

28
by commissionerleaf :: Thu, 03/17/2011 - 2:27pm

Note that DeAngelo Hall is renowned for gambling, and especially for scoring when he does. Ike Taylor couldn't catch the clap on vacation with Antonio Cromartie, but he's a good coverage cornerback.

29
by MilkmanDanimal :: Thu, 03/17/2011 - 2:46pm

"Ike Taylor couldn't catch the clap on vacation with Antonio Cromartie" may be my favorite line ever on FO. Or possibly anywhere.

31
by tuluse :: Thu, 03/17/2011 - 4:02pm

Well I think it depends on defensive philosophy more than anything. Dick LeBeau does not want to give up big plays no matter what. So he'll stick with steady corners even if they can't catch. Other defenses will gamble more for big plays, so they want the corners with good hands. Still other defenses will almost always have deep safeties, so they know getting beat really deep isn't a problem and they might choose the hands guys.

Of course this whole conversation assumes there are a plethora of different kinds of corners which teams can pick from to build their team. In reality, teams probably just get by with whoever they can.

34
by MJK :: Thu, 03/17/2011 - 5:58pm

Thing is, if you have a CB that gets burned fairly often, you don't have a decent pass defense.

What I think it depends on is the strength of your offense. Turnovers are extremely valuable, probably more so than chunks of yardage, but even for a good turnover CB, they still will happen with very low frequency. In order for the gambler CB to be better than the solid one, he's going to need to see a lot of attempts. And that means that you're going to want your offense to be good so that the other team is in "pass it a lot and play catch up" mode more.

On the other hand, if your offense sucks and the other team only needs to be careful about not turning the ball over and denying you a couple of times, then you probably want the more solid CB.

Or, put another way, if you're a careful, ball control offense with a defensive team that wins a lot of games 9-7 and 10-6, then you probably want the solid guy. If you have the Colts or Patriots offense, then you might perfer the gambler.

24
by ChicagoRaider :: Thu, 03/17/2011 - 12:55pm

And somehow the Raiders were 20th against #1 WR, and 12th against #2 WR in the defensive DVOA charts. What are we supposed to believe about the Raider cornerbacks based on that?

26
by commissionerleaf :: Thu, 03/17/2011 - 2:16pm

That opponents moved their #1 WR's around to benefit from the fact that the Raiders mostly keep their cornerbacks on a given side of the field rather than on a given receiver.

Also, I'd be curious to see what Routt's splits were in the games without Nnamdi in he lineup. Sample size theatre, obviously, but it would be very interesting if his numbers held up when he was playing effective #1 CB; certainly no other DB the Raiders have is going to scare opposing OC's.

35
by Dean :: Fri, 03/18/2011 - 9:08am

Ron Bartell really shouldn't be a surprise. He emerged as a very good player in 2008. The Rams liked him enough to sign him to a big contract extension. Granted, it's the Rams, but this was actually a rare (at the time) good move for them. He's battled injuires off and on, but when he's healthy he's played at a high level for them. Granted, it's the Rams, and if a tree falls in the woods...

But these numbers shouldn't surprise too many Rams fans.

38
by Raiderjoe :: Fri, 03/18/2011 - 10:10am

Routt grwat success 2010 season so dataa back up eye teat

40
by Bright Blue Shorts :: Fri, 03/18/2011 - 4:38pm

Wondering why Revis was targeted 57 times given his island status.

Wondering who the most targetted CB in the league was?

42
by chemical burn :: Fri, 03/18/2011 - 8:39pm

Unlike most teams with a shutdown corner, the Jets designed schemes to make throwing at Revis the most attractive option for opposing offenses - as opposed someone like Asomugh (or Samuel?) that played in schemes that said "don't even look over here." Not sure how that works on a practical level, but the Jets have said their blitz packages are designed to force throws to whomever Revis is covering...

45
by RickD :: Sun, 03/20/2011 - 11:21am

The hammy injury probably made teams want to see just how fit Revis was.

43
by foolio (not verified) :: Sun, 03/20/2011 - 9:38am

Having seen every Dolphins play of the last season, the presence of Sean Smith completely invalidates this list. He was outplayed by Jason freakin Allen who started in his place for part of the season (before being cut), and was deployed as a SS at times in nickel packages (with Vontae Davis, Benny Sapp and Al freakin Harris at the corner spots, before Harris got hurt). Sorry but this analysis is as big a joke as picking the Giants to pick first in the draft was, at the start of 2007........

44
by Shattenjager :: Sun, 03/20/2011 - 10:26am

"Aaron Schatz :: Fri, 03/18/2011 - 1:52pm

One thing I want to make clear. Both in this article, and in Wednesday's, people seem to be confusing "presentation of numbers" with "analysis." This isn't analysis. This is presentation of numbers. The ranking in a single statistical metric does not tell you a player's worth. You need to look at the whole picture in context. I'm honestly not even trying to do that in this article."

51
by mjm7187 :: Sat, 04/09/2011 - 11:46am

This is very misleading. Based of the chart the Eagles have a great cornerback tandem yet they allowed 31 passing touchdowns last year. How do you explain that?

52
by tuluse :: Sat, 04/09/2011 - 4:44pm

They have bad depth/safeties/linebackers, would be my first 3 guesses.

53
by FD147 (not verified) :: Sat, 05/07/2011 - 10:12am

And, the truly awful, Dmitri Patterson

54
by Ace23323 (not verified) :: Sun, 07/31/2011 - 10:11pm

Aaron, why does Asante Samuel in your analysis have only 36 targets with a 78% success rate, when his stat page on Football Outsider (http://www.footballoutsiders.com/player/16833/asante-samuel) has him at 38 targets with a 76% success rate?

56
by Sports-Glory (not verified) :: Thu, 08/11/2011 - 12:10pm

Good analysis of the cornerbacks from 2010.