* * * * * * *Alright, now let's look at the coverage. This is your standard cover 2. A triangle concept should work perfectly. But, OSU does roll the backside safety. He takes the slant route. Open field is between levels for the Z-receiver, so he has to get upfield of the CB and then work outside. The CB though, does a nice job (in the context of this play, I'll explain more later), to get his arms out and really re-direct Gallon. This CB has outside leverage and inside help, his goal is to tighten that window by redirecting the receiver inside, and typically, if he does that, it will help him and the defense in coverage. This redirect shouldn't happen so easily here, but the CB does his job, and it takes Gallon off track for longer than it should. Because of this, Gallon doesn't draw his flat defender outside. This is the zone-beater remember, they are running and inside-out on the flat defender here with the horizontal stretch. But the redirect makes it so the CB never has to break to the flat (with the WR even horizontally with the safety and 6 yards shallower, that safety could not defend that route alone). The redirect makes it so neither underneath DB must commit.
Let's look at what this means: if Gallon gets outside, the two underneath defenders must commit to a direction.
Flat defender stays in:
What this does is it gives DG a bad read. The window is tight, because Gallon hasn't "occupied" his defender. Because he doesn't occupy him enough to draw him out (it also doesn't allow him to commit inside, he doesn't have to commit at all rather), DG reads to throw at his chest as it reads as if that flat CB has coverage responsibility on Dileo. DG doesn't see the underneath defender because he reads the flat defender as his key for the throw to Dileo within that tight window. He's also forced to read this quickly because the pressure is getting home.
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To read much more on this play, including how OSU adjusted to stop any throw back and roll out from Gardner, as well as the other options that were available out of the stack formation, follow the link to Maize n Brew