Why some corners can’t play zone coverage
Sam Monson | June 19, 2013

Click for diagrams and full article, its worth reading the whole thing...

https://www.profootballfocus.com/blo...zone-coverage/

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When you watch tape of corners there is a clear divide between those that understand the shifting nature of zone coverages and those that don’t, but rather see them as invisible divisions on the field from which they shouldn’t stray. In this case the ball may well have been caught in Chancellor’s zone, but circumstances dictated it was very much in Sherman’s wheelhouse too, and he knew it.

At one stage in his career Asomugha was seen as such a good player that teams gave up testing him. That was made easier by the fact the Raiders would play him at RCB – the side less targeted anyway – and the rest of that secondary was a far more appealing prospect when it came to putting the ball in the air. Nonetheless, I think it’s safe to say that playing in a man-cover scheme Asomugha was a pretty good corner. Whether he ever deserved the Revis comparisons that some people were throwing around is another matter entirely. He appears, however, to have little to no feel for zone coverage, demonstrating a consistent lack of understanding for the subtle differences and changes that zone coverage requires.

This play is similar to the deep touchdown over Sherman in that the safety help Asomugha was expecting went AWOL, and he was hung out to dry to a degree. Where it differs, however, is in how each player reacted. Sherman knew instantly that there was nothing keeping him from sticking to his receiver and that his presence only made the completion harder to make.

Asomugha stuck with the route until it was leaving his zone as it was drawn up, and then even though there was nothing to keep him from playing it, he throttled down, looked around for the help that never came, and basically put it down to the mistake of a teammate.

His Eagles tenure was littered with plays like this. Unlike Sherman, Asomugha never seemed to understand how route combinations, formations and coverages could change how his zone would look on paper, or when it was actually beneficial to ignore how it was drawn up and play what he was seeing. In this particular instance he was never likely to be able to make much of a play on a well thrown ball, but on anything less he could have been in position to make a play, rather than giving up because it was no longer in his zone.

As if to prove the point, the next play comes in similar circumstances, but this time the play is made by a player who had no right to be anywhere near it. The Falcons line up with just a single wide out, split to the left. As Matt Bowen pointed out to me on twitter, when he was playing and teams would do that his defenses would break out all kinds of funky coverages to try and take away that single receiver, or at least confuse the quarterback out of targeting him. Oakland looked to bracket Julio Jones, and on the other side of the field they had Tony Gonzalez taken care of over the middle as well. That left Michael Huff, playing LCB with practically nothing to do on the play.

Instead of switching off and watching the action unfold, he kept gaining depth and looked for work. He recognized the potential of a deep crossing route and his quick thinking and hustle paid off to the tune of an interception that Matt Ryan cannot possibly have been expected to see coming.

Zone coverage might in theory seem like a much easier defense to play than man coverage, because you’re watching the quarterback most of the time, but these plays show there is more to it than that. Corners need to be able to understand route combinations, alignment, and tendencies, and have to learn when zones change from how they’re drawn up on the chalkboard.

It may be physically less challenging at times, but zone schemes can be far more mentally demanding than simply sticking to your receiver like glue and preventing the catch. Some players have that ability to think quickly on their feet and adjust or modify their assignment on the fly, others just don’t.