An NFL Draft Blog

An NFL Draft Blog
Formerly known as the player rater.

Sunday, December 19, 2010

The validity in the "yards allowed," statistic for corners.

I have always been pretty back and forth on how valid talking about how many yards guys like Justin Blackmon got on Prince Amukamara in the Nebraska Oklahoma State game this year. Does Blackmon getting 157 yards in that game really mean anything? Or is Amukamara often lining up on one side of the field, and is he not necessarily facing Blackmon? Well, I decided to test the validity of that statistic. I figured that if there is validity in the statistic, then corners who that allow a small amount of yards per game according to the statistic should be drafted higher than corners whom allow a lot of yards per game according to the statistic. I decided to see how many yards per game each corner expected to be drafted allowed to number one receivers, excluding games against FCS teams or games decided by 21 points or more, in which a corner may be subbed out pretty early in the game and his backup used to avoid injury, or the team with the lead stops throwing the ball because their lead is so great. I figured, that if the top corners in the FBS did well in this statistic, then the statistic is valid. Here are my results.

Once you factor in the fact that guys like Johnny Patrick and Brandon Hogan play in the Big East and their stats shouldn't be taken quite as seriously, it's pretty clear that corners that did well in the statistic were projected to be drafted higher than corners who weren't, with only three players that could be considered exceptions: Prince Amukamara, Patrick Peterson, and Darrin Walls.

I am not going to sit here and bash Amukamara. If Amukamara is examined more closely, it's clear that he wasn't as bad as the stat suggested; 42% of his yards allowed came on 3 single catches. The 80 yard pass to Justin Blackmon, for example, was a flea flicker, and it would not have gone for quite as many yards if Amukamara had made the tackle that he missed, Oklahoma State wasn't at its own 20, or if the safety that was fooled by the flea flicker had stayed in position to make the tackle. Though I do think Amukamara is overrated, it's actually because he has mediocre production for a first round prospect, and he doesn't have the jaw-dropping physical tools that can make up for the above average overall production, but still mediocre for a first round pick. He is 6'0 with a 4.49 40 yard dash, which is completely average, but far from the "once in a lifetime," talent a corner should have to be a mid first round pick. Now, if he allowed 35 yards per game I would concede that he was dominant enough to make up for those average physical tools, but he didn't, and he isn't dominant enough to make up for those physical tools.

Peterson frankly doesn't surprise me. I have always said he was extremely overrated, and, to tell the truth, I could have booked him for 81.4 yards allowed per game if I had counted the North Carolina game against him. I couldn't really get an idea whom North Carolina's number one receiver was during that game. Though Dwight Jones ended up leading that team in receiving yards, he only got 104 yards in the first 5 games combined, and didn't appear to be the number one receiver at the time. It was either Jheranie Boyd or Erik Highsmith. Boyd ended up getting one more yard than Highsmith on the season, and if I had counted Boyd's numbers against Peterson in that game, it would have been an extra 221 yards to his tally, and an extra 23.2 yards per game allowed. But I don't think I am going to count the fact the Boyd got one more yard than Highsmith against Peterson. But what's undeniable, it would be pretty tough for Boyd to get 221 yards in a game without being the number one receiver.

And finally, Darrin Walls always seemed really underrated to me. Not only did he master pretty good production during the 2010 season, but he is 6'0 tall and runs a 4.45 40 yard dash. I realize that isn't amazing, but guys like that don't grow on trees, either, and they're hard to find in the 7th round. He has always seemed pretty underrated to me because of that production, solid physical tools, and the fact that Notre Dame plays a pretty tough schedule. I'll get more into him later.

Some doubters will say that I gave Aaron Williams too high a projection by putting him in front of Brandon Harris, Davon House, and even to some extent Donnie Fletcher. Though I think Harris and House are better than Williams, most NFL draft scouts will say Williams has a more cover skills than the two. Much of the reason that Williams will be a late first round prospect instead of an early first round prospect is because of his horrible lack of strength, physicality, and ability to stop the run. He got 31 tackles last year at Texas, by far the worst of any corner that will be drafted this year. His unbelievable ineptitude when it comes to stopping the run and making tackles makes him a late first round prospect, and a little behind Harris and House in draft position.

I realize that people will doubt the validity of the statistic. Don't write me off quite yet. The statistic appears valid according to those results. I know people are going to ignore the statistic, and say that corners too often line up on one side of the field, but try to remember the fact that coaches are going to want a real dominant corner on a real dominant player. For example, if you are Urban Meyer (or, I guess Will Muschamp), and you are facing Georgia, you are going to want a corner as dominant as Janoris Jenkins matched up against A.J. Green as much as possible, and your second corner, sophomore Jeremy Brown, matched up against Green as little as possible. If you watched the Florida Georgia game closely, you would clearly see that Jenkins never leaves Green. He gets and interception off of him and holds him to a mere 42 yards, his worst game of the season. Without watching the game, should I even have to ask my readers if they are going to contest the idea that Jeremy Brown played a large role in stopping Green? I don't think so. It was clear that Jenkins was matched up against Green, and using that game in Jenkins' favor is completely valid. Now, if a coach has two corners that are practically interchangeable, such as Virginia's Ras-I Dowling and Chase Minnifield, then the statistic is invalid. Each corner will match up against the number one receiver at different parts of the game. But let's be honest; take the Alabama LSU game for example. Les Miles would eat grass before he let true sophomore Morris Claiborne line up against Julio Jones when he has Patrick Peterson on the roster (okay, that was a bad example). But still, there is no way he would let Claiborne line up against Jones if he can make Jones line up against Peterson. Julio Jones got 89 yards in the game. For the sake of proving my point, after I wrote this article, I watched the game. I used KC Joyner's sabermetrics of figuring how many yards Peterson allowed and how many yards he gave up per throw, and watched every ball Greg McElroy threw. Julio Jones had 6 of his 9 catches against Peterson (he had 10 catches on the game, but one was while Peterson was on the sideline, taking a one play breather), for 52 yards, and Peterson also allowed a 37 catch to Marquis Maze in the game (Technically, the catch didn't count. Peterson did a blatant pass interference on Maze, pulling his right arm around his back, and the officials ruled he made a one-handed catch, but when the play was reviewed, they ruled it wasn't a catch. Peterson still got a 15 yard pass interference penalty called against him, but at the NFL level, that's a 37 yard penalty. Considering I'm evaluating him for the NFL, I'm considering that a 37 yard catch). So let's add that up; 37 yards for Maze, 52 for Jones... that's 89 yards! Coincidentally, the exact number the stat counted against him. That stat isn't usually going to be that perfect, but I think it is good enough to be considered valid. Miles did try to make sure that Peterson was lined up against Jones as much as possible. Jones still got yards. It was Peterson's fault that he did. Now, are you going to tell me that stat is invalid? Please.

Overall, I think there is enough validity in the statistic for me to feel comfortable about using it to evaluate corners to some extent during the draft process. Clearly corners that did better in the statistic were considered better players by the draft community, and I think it makes the stat reasonably valid.

8 comments:

  1. Have you run numbers on previous years? To see how numbers

    match up versus NFL performance?

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  2. Took me 3 days to do this. Maybe later.

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  3. Very interesting. I think you may be on to something. When will you come out with your Mock draft?

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  4. It will be a while. Right now, I am watching as many college football games as possible (I have 3 TiVo's and I see 225+ games a year), and then I will make a scouting report similar to my others for the top 300 prospects of the draft. I write more scouting reports than anyone in the country does without any help or any staff, so I don't expect to be done until a week or two before the draft. As soon as I take care of that, I'll make a 7 round mock.
    Thanks for the comment, and I am glad you enjoyed the article.

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  5. To be more specific, right now, I have about 30 games left on the TiVo's, so I think I'll be done by around January 14th. After that, I'll start writing about 3 scouting reports a day, and I'll hopefully be done around April 18th. It will probably take a day or two to make a 7 round mock draft, So I think you can expect it around April 20th.

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  6. dude every catch Boyd had in that game against LSU were big plays against Morris Claiborne and a freshman corner that had just switched positions this past spring, you have no idea what you are talking about. WATCH the games and than post.

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  7. Peterson didnt play but maybe two series in the 2nd half of the game, LSU had taken their starters out at halftime because of the score (even though it was far too early to do so)you amaze me at times...

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  8. I see that you DID NOT WATCH THE FLORIDA VS GEORGIA game eith, Green was bracketed 90% of the game, Florida's COVER 2 BASED!!!!

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