WMU stunt blitzes

While rewatching the game yesterday in an effort to track Will Campbell's game time and performance (which were limited and not very encouraging, respectively, and not nearly interesting enough for the full post I had intended on writing), I came across something far more interesting. After diagramming two blitzes that Michigan used on Saturday, both structured around a linebacker stunt and overloading one side of the offensive line, a few commenters wondered whether or not a more competent offensive line might be able to more effectively block the blitzes. Their arguments:

The mistake is buy [sic] the play side guard and center. The guard needs to slide out to take Kovacs and the center take Brinks. When the center sees Heinenger bail into zone, it's obviously a zone blitz and he needs to find the blitzing side and get the guard wide to pick up the safety. With and experienced line who has gelled and knows how to identify and pick up blitzes, this won't work nearly as well.

and

I recall: 1) later the D looking something very similar to this and Kovacs dropping back and getting a tip; and 2) the D turning into a near feeding frenzy as the WMU OLine seemed so confused play after play. Hopefully this is the Mattison effect and it continues into the season.

Fortunately, Western ran an almost identical blitz early in the second half.

Michigan is in a four-wide set with Vincent Smith in the backfield. You may recognize the defensive alignment from the blitzes diagrammed earlier. Western Michigan is crowding the line of scrimmage with linebackers in an effort to disguise coverage and where the blitz is coming from. Much like the plays Michigan ran, WMU is in a three-lineman set with a NT covering the center and three men outside of the offensive guards (in this instance, we'll be watching the weakside blitz [top of the screen]).

As the ball is snapped, Western blitzes all seven men on the line of scrimmage. The outermost linebackers for WMU begin to stunt inside.

As you can see, Taylor Lewan is blocking the edge rusher, Michael Schofield is blocking the WDE, and David Molk is blocking the NT, leaving a hole in the A gap for the stunting WMU linebacker to blitz through unblocked.

As the WMU blitzer shoots the A gap, blocker extraordinaire Vincent Smith recognizes the weakside blitz and steps in front of Denard to make the block.

Smith steps up and chops down the WMU defender, allowing Denard to get the pass off (it will fall incomplete to Roundtree, mostly because this was at the beginning of the torrential downpour).

I think we all would agree that Michigan's offensive line is more cohesive and talented than Western Michigan's, yet the Broncos were still able to get essentially a free blitzer into the backfield with the same stunt principle. Fortunately, Smith chops the blitzer before he can cause any real damage, but the schemes are what I'm concerned with. Notice also that WMU executed this stunt blitz on the strongside of the field as well. You can the WMU linebacker #29 about to shoot the strongside A gap between Molk and Omameh completely unblocked.

Obviously, there are some differences between this play and the ones Michigan ran. First of all, the WMU nose tackle rushed rather than dropping off into coverage. This changes the play in a number of subtle ways. Whereas Michigan blitzers Kovacs and Demens shot the B gap (between the guard and tackle), the WMU blitzers were attacking the A gap (between the guard and center). In my opinion, this probably made it easier for Smith to recognize and block the weakside blitz as he only needed to step up in the pocket rather than come across the face of his QB.

Secondly, with or without the NT dropping into coverage, it's the guard's responsibility to block the defensive end shaded to his outside shoulder. Given that there are three players outside of the guard, including a DE at the 3-tech spot, it's the guard's responsibility to block that DE while the tackle is responsible for the edge rusher, and the running back is responsible for the stunt blitz. In this play, we see Schofield block the weakside DE (Omameh blocks the SDE), Lewan blocks the edge rusher (as does Huyge on the strongside), and Smith steps up to take out the blitzer stunting to the middle. When Michigan used this concept, the NT dropped into coverage and the WMU center doubled the DE. This necessitated that Michigan blitz the B gap instead of the A gap as WMU does here.

The point is that Mattison's defensive principles are sound and will work independent of the opposition's skill level or coaching. The chances that Michigan can land the punishing sacks that they did against WMU against better opposition is unlikely as more skilled running backs will probably make the block that Smith does here, but I'm willing to risk sending Kovacs or Demens full bore against a running back in the backfield.

UPDATE
Per a commenter's request, here's video of the play in question (:41 mark)


For what it's worth, I'm still working on getting an open source video editor to do this myself.