When evaluating cornerbacks, I gather as much game film as I can, and then chart every play that they are involved in. Doing this helps give context to statistics. Instead of looking at how well the opposing receiver performed, I want to see what coverages the defensemen lined up in. Having scheme versatility is important, but if a player excels in once scheme, a team can then put the player in a position to consistently win.
What exactly do I chart? Well, take a look at the table below. This shows the amount of man, off-man and zone coverage. Also, did they press? How many times did they “win”, “lose”, or “no decision”?
By “win”, that means the corner either knocked the pass down, made the interception or had excellent coverage on the play. The receiver can still make the catch and the corner still “win”, because sometimes there’s nothing more a receiver can do. If a cornerback is within arm length of the receiver and has their head turned toward the ball, it is rare that they’ll earn a “loss”.
“No decision” means that the play didn’t go anywhere near the corner, but he wasn’t in an obviously bad position if the pass did go that way. I assume the corner didn’t lose since the play didn’t go that way.
A “loss” counts as a “burn”, and the corner was clearly beaten on the route for any possible reason. More than one yard of separation is a clear burn. The rest is subjective using strict
Typically, if a corner posts a burn percentage of less than 11%, they had an elite year, even if it was in one certain coverage. Anything around 20% is very good. Greater than 30% is average to poor.
Please feel free to comment on this post or tweet at me @NFLFilmStudy. I’d be happy to discuss more about why this measurement is effective.