For those of you who are new to BWSblog.com or those who haven't been around for a while, the majority of the content during the season is focused on diagramming plays and making sense of why and how things happen on the field.
If the Baltimore Ravens' defense of the last few years is any indication, watching this year's defense will be a ton of fun. The Ravens are notorious for bringing pressure from all over the field and having defensive schemes that give offensive lines fits. Though the game against WMU got off to an inauspicious start, Greg Mattison started to show some of those defensive schemes that Michigan fans have been waiting for.
After a three and out to start the second half, Michigan punted the ball away to the Broncos who began marching down the field. After a bobbled snap, the Broncos were in a 2nd and 12 situation.
Michigan comes out with three down linemen in the game: Mike Martin as the WDE, Ryan Van Bergen as the NT, and Jibreel Black as the SDE. With that personnel, it's clear that Michigan is expecting a pass. Jordan Kovacs and Brandon Herron are on the line of scrimmage, showing a weakside blitz. The team is in a man coverage look with one deep safety. WMU is in a three-wide set with a tight end lined up as an H-back and a RB flanking Alex Carder.
Just before the snap, Michigan's defensive line shifts to the strongside of the field. Black is now playing the 5-tech, shaded just outside the left tackle; Van Bergen is playing the 3-tech, shaded just outside the left guard; and Mike Martin is playing the 1-tech on the weakside of the line. Kenny Demens has moved from his position as the MLB to the 7-tech spot, shaded just outside the H-back. This shift has changed the pre-snap read from a weakside blitz to a strongside blitz.
When the ball is snapped, WMU's H-back takes off running a seam route. He will be picked up in man coverage by Jared Van Slyke who is on the field as a nickel linebacker. On the strongside of the play JT Floyd has man coverage on the outside receiver and Thomas Gordon is covering the slot receiver. On the weakside, Jordan Kovacs drops into coverage after showing blitz presnap. He and Courtney Avery have bracket coverage on the weakside wide receiver. Herron will also drop into coverage, picking up the RB in man coverage. Despite looking like a cover-1 formation presnap, Michigan is in a cover-2, man under defense.
On the line, Martin, Van Bergen, Black, and Demens all rush the strongside. Martin attacks the right guard, Van Bergen goes directly at the left guard, and Black shoots directly upfield past the left tackle. Demens will stunt behind Black into the hole created by Black and Van Bergen's rush.
As you can see, Floyd has pressed the strongside WR to the outside. Gordon is engaging the slot receiver, Van Slyke is stepping up to cover the H-back, and Kovacs has dropped off into coverage to bracket the weakside receiver. Carder's first read is to the strongside. Here, he sees that all of his receivers are tightly covered with safety help over the top. Next, he'll turn to his weakside receiver who is running a hitch route.
As you can already see, the left tackle has taken the bait and stepped downfield, and Van Bergen is engaged with the left guard. This creates a massive hold for Demens to scream through.
At this point, the center and left guard are doubling Van Bergen and Demens has a clear shot at Carder. The RB is still expecting the weakside blitz that Michigan showed presnap and doesn't see Demens blitzing from the strong side. Carder's weakside receiver is being bracketed by Avery and Kovacs.
Demens is now free on the strongside and screaming at Carder's blind side. Van Bergen has shed his blockers and is headed into the pocket should Carder step up. The left side of the offensive line is either falling down or doubling Black. The strongside receivers are all blanketed by their matchups and the weakside receiver is surrounding by Kovacs and Avery.
Carder finally feels the pressure from Demens and steps up into the pocket where Van Bergen is waiting for him. Demens is now in pursuit and will help corral Carder with Van Bergen
The play ends as a three-yard rush as Carder falls forward, but this play worked exactly as planned: confuse the offensive line with a presnap shift and stunt in order to get quick pressure on the QB and induce a quick throw to a covered receiver or force a scramble/sack. Fortunately, the gods of replay give us a great look at the defensive line's alignment and how the stunt worked.
As you can see above, Van Bergen is shaded to the outside of the left guard (#65), Black is outside the lef tackle (#72), and Demens is outside the H-back (#46). A moment later, Demens will drop behind Black and scream into the backfield:
You can see the left tackle being drawn outside by Black who doesn't even look like he's trying to get to Carder, while Van Bergen takes on the left guard/center double team. This leaves Demens unblocked.
Michigan did almost the exact same play later in the drive (which I'll show tomorrow) with Kovacs blitzing from the weakside. On that play, the blitz actually landed and caused Carder to fumble. Mattison is using stunts and mismatches to get unblocked blitzers. By overloading one side of the field, the offensive line is unable to block everyone. This forces Carder to either make a quick throw or take a sack. Mattison uses the stunt here to get Demens a more direct route to the QB. Demens could have just as easily tried screaming around the outside of the left tackle, but this play design opens up a direct line for Demens.