by Aaron Schatz
With some downtime between the Championship games and the Super Bowl, I thought it would be interesting to take a look at our game charting stats for cornerbacks in 2008. Unlike the numbers which will appear in Pro Football Prospectus 2009, these stats haven't yet been adjusted for opponent, and they don't account for zone coverage and double coverage. Right now, I'm simply judging by which defender the charter lists in the DEFENDER1 column. Plays marked Hit in Motion, Tipped at Line, or Thrown Away were removed. I also removed screen passes, because if a cornerback is blocked off the line during a wide receiver screen, that's not really indicative of his ability to cover his man on a standard pass play.
Rather than use a minimum number of charted passes to be ranked, I tried to just take out cornerbacks who primarily played the nickel. In general, that meant players who played the whole season but didn't start at least half their team's games. The top nickel backs of the season included William Gay of Pittsburgh, Joselio Hanson of Philadelphia, and a player who had done terrible in these numbers in the past, Kevin Dockery of the New York Giants.
Here are the top 10 starting cornerbacks in terms of Success Rate [1]:
| Player | Team | Charted Passes |
Yd/Pass | Success Rate |
| 31-A.Harris | GB | 38 | 5.0 | 79% |
| 24-S.Brown | PHI | 55 | 4.6 | 73% |
| 21-C.Woodson | GB | 57 | 6.4 | 66% |
| 22-S.Rolle | BAL | 40 | 4.4 | 65% |
| 26-A.Winfield | MIN | 59 | 6.0 | 64% |
| 21-N.Asomugha | OAK | 26 | 5.8 | 64% |
| 23-C.Webster | NYG | 65 | 5.1 | 63% |
| 22-C.Rogers | WAS | 92 | 5.6 | 63% |
| 24-D.Foxworth | ATL | 48 | 5.6 | 63% |
| 20-N.Harper | TEN | 90 | 5.7 | 62% |
In 2007, we called Al Harris' Pro Bowl selection a "lifetime achievement award." He finished 74th in Success Rate, 73rd in Adjusted Yards per Pass (I'm listing here the adjusted numbers from Pro Football Prospectus 2008). Although he was injured for part of 2008, he clearly rebounded to his previous level of performance when he was healthy. His numbers would be even better without the fourth quarter of the relatively meaningless Week 17 game against Detroit, when he gave up a combined 82 yards on three complete passes to... yikes... John Standeford.
Washington fans are probably surprised to see that Carlos Rogers comes out among our top cornerbacks in charting. Rogers basically lost his job to DeAngelo Hall by the end of the year, and is apparently being dangled in trade talks as the Redskins try to pick up some extra draft picks. (How often do you read that sentence?) Here are the overall charting numbers for the four Washington corners:
| Player | Team | Charted Passes |
Yd/Pass | Success Rate |
| 22-C.Rogers | WAS | 92 | 5.6 | 63% |
| 23-D.Hall | WAS | 24 | 3.2 | 67% |
| 24-S.Springs | WAS | 34 | 6.3 | 53% |
| 27-F.Smoot | WAS | 56 | 8.7 | 38% |
Wow! Look at those numbers for DeAngelo Hall! That's awfully impressive... except that it only represents half a season. In the other half of the season, over in Oakland, DeAngelo Hall has 56 charted passes with 9.0 yards allowed per pass and a 43 percent Success Rate. The danger here is that the Redskins are falling in love with a small sample size, at the risk of bailing out on a talented young player. It sounds good to go with Hall and Shawn Springs as your starters, but Hall has never had an extended performance that came close to what he did over the second half of the year in Washington, and Springs always has injury issues (although he always plays well when healthy). There's no question that Rogers was better in the first half of the season (66%, 5.3 yd/pass in Weeks 1-9) than he was in the second half (57%, 6.2 yd/pass in Weeks 11-17) but those second-half numbers aren't exactly poor. Furthermore, Fred Smoot's performance as part-time starter and part-time nickel doesn't exactly deserve wreaths and flowers. If I were running the Redskins, I don't think I would be in a rush to trade Rogers.
As for Hall's old teammates in Oakland... Nnamdi Asomugha may not end up with the best charting stats, but his target numbers are just plain sick. Compare Asomugha to the other players on this list with a low number of charted passes. Al Harris, for example, has 38 charted passes, but he only played 12 games. That's 3.2 charted passes per game. Samari Rolle has 4.0 charted passes per game. Asomugha played 15 games this season... which means he has only 1.7 charted passes per game.
Here are the top 10 starting cornerbacks in terms of Yards per Pass
| Player | Team | Charted Passes |
Yd/Pass | Success Rate |
| 22-S.Rolle | BAL | 40 | 4.4 | 65% |
| 24-S.Brown | PHI | 55 | 4.6 | 73% |
| 31-A.Harris | GB | 38 | 5.0 | 79% |
| 24-B.Flowers | KC | 60 | 5.1 | 55% |
| 23-C.Webster | NYG | 65 | 5.1 | 63% |
| 29-D.Rodgers-Cromartie | ARI | 64 | 5.4 | 52% |
| 26-K.Hayden | IND | 45 | 5.5 | 60% |
| 22-C.Rogers | WAS | 92 | 5.6 | 63% |
| 24-D.Foxworth | ATL | 48 | 5.6 | 63% |
| 20-N.Harper | TEN | 90 | 5.7 | 62% |
How about that Brandon Flowers! The average pass against Flowers (9.3 yards) was much shorter than the average against most starting cornerbacks (roughly 11.5 yards) but still, that's pretty good for a rookie, certainly better than his rookie partner Brandon Carr.
Here's one more interesting statistic, one I looked at this season for the first time. Here are the best cornerbacks in terms of Stop Rate when making tackles on complete passes... in other words, which cornerbacks still do a good job of preventing success, even when they allow a completion. This can be a good way to analyze some of the Cover-2 cornerbacks who are supposed to allow completions as long as they keep those completions in front of them. The top ten among cornerbacks with at least 30 pass tackles...
| Player | Team | Pass Tackles | Stop Rate |
| 26-A.Winfield | MIN | 56 | 45% |
| 35-C.Ivy | BAL | 33 | 42% |
| 20-A.Cason | SD | 50 | 40% |
| 20-B.McFadden | PIT | 34 | 35% |
| 22-N.Clements | SF | 40 | 35% |
| 20-N.Harper | TEN | 55 | 35% |
| 20-R.Barber | TB | 47 | 32% |
| 24-S.Brown | PHI | 31 | 29% |
| 22-C.Rogers | WAS | 45 | 29% |
| 34-D.Lowery | NYJ | 55 | 27% |
Now let's look at the worst cornerbacks of the year according to the game charting. Here are the bottom 10 starting cornerbacks in terms of Success Rate:
| Player | Team | Charted Passes |
Yd/Pass | Success Rate |
| 25-B.Kelly | DET | 37 | 11.6 | 32% |
| 23-T.Jennings | IND | 57 | 8.6 | 37% |
| 27-F.Smoot | WAS | 56 | 8.7 | 38% |
| 21-T.Fisher | DET | 36 | 9.3 | 39% |
| 22-J.Joseph | CIN | 40 | 8.2 | 40% |
| 28-L.Bodden | DET | 76 | 9.0 | 41% |
| 39-B.Carr | KC | 76 | 8.8 | 41% |
| 21-C.Graham | CHI | 62 | 7.7 | 42% |
| 32-D.Bly | DEN | 80 | 8.4 | 43% |
| 32-F.Bennett | HOU | 47 | 7.7 | 43% |
Yes, three Detroit cornerbacks show up in the bottom ten. Each of these guys started for a large part of the season; the Lions started Kelly for 11 games and then just cut bait on him after Week 12. Good move there. You've also read a number of comments on Football Outsiders this year about the fall of our former cornerback binky, Leigh Bodden. We used to promote him as perhaps the league's most underrated cornerback; this year, he was one of the worst. Obviously, some of the issue with the Detroit cornerbacks is the overall defensive performance -- there wasn't exactly a lot of pass pressure to help them out -- and we're hopeful Bodden can find his way back to at least league-average under the new regime.
Unfortunately, Bodden isn't the only one of our favorite underrated cornerbacks who hit the skids in 2008. In Pro Football Prospectus 2008, we pointed out the outstanding rookie performance of Houston's Fred Bennett, a fourth-round pick out of South Carolina who put up some of the best game charting numbers in the league. We expressed shock when the Texans benched Bennett a few games into 2009. How on earth could they think Demarcus Faggins was a better cornerback than Bennett? Well, this is how. The better question is, what the hell happened? That's a question probably better answered by scouting than by stats, but it is something to certainly explore this offseason.
Here are the bottom 10 starting cornerbacks in terms of Yards per Pass:
| Player | Team | Charted Passes |
Yd/Pass | Success Rate |
| 25-B.Kelly | DET | 37 | 11.6 | 32% |
| 20-R.Barber | TB | 75 | 10.1 | 44% |
| 21-K.Jennings | SEA | 64 | 9.8 | 47% |
| 21-T.Fisher | DET | 36 | 9.3 | 39% |
| 38-T.Williams | GB | 65 | 9.2 | 49% |
| 28-L.Bodden | DET | 76 | 9.0 | 41% |
| 41-T.Newman | DAL | 50 | 9.0 | 44% |
| 31-A.Ross | NYG | 76 | 8.9 | 50% |
| 29-L.Hall | CIN | 86 | 8.8 | 43% |
| 22-B.McDonald | CLE | 81 | 8.8 | 46% |
It's been an off-year for Terence Newman, who certainly was better in years past. You can also see here some very clear distinctions between two cornerbacks on the same team. Quarterbacks had a reason to target Aaron Ross over Corey Webster, and to target Tramon Williams over either Al Harris or Charles Woodson, depending which one was actually playing at the other cornerback spot.
Finally, here's the look at the cornerbacks with the worst Stop Rate on pass tackles:
| Player | Team | Pass Tackles | Stop Rate |
| 32-F.Bennett | HOU | 31 | 13% |
| 39-B.Carr | KC | 46 | 13% |
| 34-F.Brown | STL | 30 | 13% |
| 24-R.Bartell | STL | 36 | 14% |
| 28-L.Bodden | DET | 56 | 14% |
| 35-J.Reeves | HOU | 42 | 14% |
| 23-D.Hall | OAK/WAS | 52 | 15% |
| 20-R.Gay | NO | 31 | 15% |
| 29-L.Hall | CIN | 52 | 15% |
| 31-P.Buchanon | TB | 39 | 15% |
Looking at this year's numbers in comparison with last year's numbers, one thing that stands out is the year-to-year inconsistency of many of these cornerback statistics. Al Harris is up, then down, then back up. Samari Rolle was the worst cornerback in the league by these stats two years ago. Fred Bennett goes from one of the best to one of the worst. The same thing happened to Lito Sheppard, who has awful stats in 2005, great stats in 2006, and then awful stats again in 2007 and 2008. It's reasonable to wonder just how meaningful these stats are when some players seem to oscillate wildly from one extreme to the other.
We now have four years worth of charting data, and one thing we can do in this coming offseason is look at cornerbacks over two- and three-year periods. Perhaps a larger sample size will create more consistency. It's worth noting that the top cornerbacks in the league generally come out with good charting numbers each year, even if they don't show up in the top of the rankings each year. Asante Samuel had good numbers this year (59%, 6.3 yd/pass). So did Shawn Springs (53%, 6.3 yd/pass) and Pacman Jones (59%, 5.7 yd/pass). Champ Bailey had excellent numbers in the first three years of charting, even if he was not at the very top of the league each year. Bailey did not have good numbers in 2008 (37%, 11.8 yd/pass) but that doesn't tell us much, as he was out for much of the year and clearly playing hurt when he returned. Bailey has only 19 charted passes; six of them are in Week 16-17, all complete, for an average of 18.2 yards. Clearly, he came back too early as the Broncos desperately tried to stop their late-season collapse.
If we can figure out how many years of good charting stats it takes before we can trust that a player is consistently good, we'll do a better job of not jumping to conclusions about rookies like Fred Bennett. Whether the Washington Redskins can keep from jumping to conclusions over a half-season of DeAngelo Hall, however, is up to the Redskins.
Links:
[1] http://www.footballoutsiders.com/info/glossary#defense_success_rate