One thing that teams have started to do against Michigan in an attempt to stop the zone read is run their defensive end directly upfield and blitz a linebacker in the resulting gaps. We first saw this last week against Illinois. MGoBlog Picture Paged two different plays in which Illinois showed the defensive front and how Michigan adjusted to it. The first instance ended in a rush for zero gain. The second time, Michigan completely disregarded Illinois' defensive end and sent H-back Martell Webb to block the blitzing linebacker. It looked like this:
Purdue deployed a similar tactic, but rather than blitzing the zone vacated by the defensive end, they blitzed up the middle of the formation, opening up the 19-yard Vincent Smith rush. The really interesting thing here is the read that Denard makes.
There are a few interesting things here. Michigan clearly gameplanned for Purdue to send their defensive ends upfield and made sure they had a blocking scheme for it. Since they did, Shaw stayed in the backfield to chip Kerrigan, and Denard was supposed to read the blitzing linebacker. If Kerrigan didn't run into the backfield, Shaw would've been responsible to block the unblocked linebacker, and this probably would've been a passing play (about more which in a second).
The next thing to notice is who Denard was reading: on a lot of the plays that look like direct handoffs, Denard is actually reading the linebackers like he does here. Most of the time, linebackers aren't crashing down on the play, so it looks like a direct handoff. But here, Denard is forced to make the read, and fortunately makes the proper one.
The most frustrating thing for Purdue here, is that if the linebackers had attacked Smith instead of Denard, this is probably a four-yard loss. You can see in some of the early screen captures that the receivers are actually running routes, not blocking downfield for a run play (much like the Roundtree touchdown against Notre Dame). This means that if Denard keeps the ball here, it's probably a pass play in which there's significant penetration into the backfield. Instead, Denard is able to bait the blitzing linebackers into playing him instead of Smith, opening up the running lane.
Frankly, there's a lot of stuff going on here and it's difficult to sort through. I'm usually fairly confident that I know exactly why a play happened the way it did, but I'm a little less sure of this one. Anyone with some expertise, feel free to let me know if there's something I'm missing here.