Last year Wisconsin messed with Michigan gap defense plenty, but even that wasn't as bad as Michigan's Lovie Smithian edge defense on Saturday. As you might have guessed, such a wholesale disaster was the result of many issues. But I did find one play that included most of them.

This is a simple jet sweep, and a fine example of what an absolute disaster Michigan's run defense has become this year. The simple explanation for what went wrong on this play is that Michigan cracked but did not replace. They spilled without an edge. Gemon Green was the main issue but other culprits here who had a chance to make a play and didn't were Daxton Hill, who got crack-blocked by the WR, Brad Hawkins, who instead of funneling back to help got taken for a donkey ride, Donovan Jeter who didn't read the handoff and pursue, Carlo Kemp who didn't do enough to keep his LB clean, Josh Ross who got caught inside and then shoved to the ground, the refs because the shove was in the back, and Vincent Gray because he's Vincent Gray. Blame goes on the players yes, but also very much on their coaches, particularly whoever's coaching the safeties, because these issues were chronic.

[After THE JUMP: Spilling to nothing]

Playing to Spill

First a quick refresher on Crack/Replace, aka Playing to Spill:

Playing to spill is a defensive technique where the force player (edge defender) dives inside of a block while another defender pops outside. This is done on the fly as a way to screw up blocking assignments and force the ballcarrier into this now-unblocked outside defender.

You can see it executed here against Maryland last season. Hutchinson (#97) spills McGrone (#44) who spills to Hudson (#7) who spills to Metellus (#14) who now has the back trapped against the sideline.

The trick is of course that you need that speed to come through. If your defense is relying on the linebackers not getting outflanked, anything that delays the linebackers inside is going to turn the strength of their speed into a weakness.

Defending Jet

Using that structure, how is Michigan supposed to defend a Jet Sweep like this?

It's simple enough: keep replacing on the edge until there's nobody but the ballcarrier and the sideline.

However Michigan is at a disadvantage at the snap because their linebackers—plus Daxton Hill who's basically been turned into the Viper on this play—are all looking inside. The cornerback, Gemon Green, is focused on the WR in man defense. Only Hawkins, traveling with the Jet motion, is stepping playside.

Who's supposed to be looking out depends on how you defend things. If we were watching MSU here you'd be mad at the defensive line for getting reached by the LG and LT. But Michigan's defense is a crack-replace. The line is supposed to go inside of those blocks, and the linebacker level is supposed to make them right by getting outside.

The reason I put this partly on Dax is he's the defender supposed to make Kemp right. Getting crack-blocked by a wide receiver while the guy (the H-back) you're nominally defending gets to the edge is losing the play. Dax getting blocked to Bolivia by that WR creates an obstacle for Josh Ross, who needs to make Jeter right by getting outside this guard.

Ross got blocked in the back here but that doesn't happen if Hill isn't stacked up in his path.

However Michigan has another guy who's supposed to be helping here. The guy on the other side of the WR blocking Dax is CB #22 Gemon Green, who makes the classing Channing Stribling mistake: DON'T GET STUCK ON A DOTGAMNED CRACKER!

Watch #22 on the top this time.

If Dax's mistake is one of unawareness, Gemon's is two ticks worse. The phrase "Crack/Replace" comes from this technique every cornerback should learn in high school for run defense. This was an issue from the first snap of the game. I clipped this for the next section because of what happens to Cam McGrone, but it's also hard not to notice Green getting caught inside then falling down.

Lastly I want to cluck at Carlo Kemp, mostly because we saw Gabe Newburg play it better later on.

Defensive end at the top

The guard who picked off Ross the first time can't get out there because Newburg decided to cut off that guy instead of just hanging on the shoulder of the offensive tackle. Neither is able to make the play, because they're both quasi-tackles. You think back to Chase Winovich versus Maryland in 2018 when Matt Canada kept trying to edge Michigan with their Flexbone offense, and couldn't because the end couldn't get turned. The lack of an elite DE is a recruiting issue, though one most teams have to face. The reason the same play got six yards on this second example wasn't Newburg or Ross, but Michigan playing Cover 2 and Vincent Gray getting blown up on the edge with a receiver's kickout block. The reason Michigan can't get away with those kinds of mistakes is they have way fewer All-Americans available this year than they've had in the past.

Getting Favorable Matchups

Wisconsin knew what they were doing when they set this up. It's the same thing Mark Dantonio was doing in the "July Drive" against Michigan in 2016: flip the strength of the formation to get favorable matchups.

They come out in their Ace Heavy formation with a pair of tight ends on the boundary side. Michigan sets their strength to personnel, so the Anchor—now Carlo Kemp with Hutchinson and Paye out—will be between that big heavy tight end and their viper, Michael Barrett, who's a hybrid safety who can play and old-fashioned strongside OLB because he's willing to hit like a linebacker, and the bigger defensive end protects him from direct blocks.

When Wisconsin flips the inline tight end, Barrett travels to the other side, and the other two linebackers flip so that WILL James Ross is still the OLB and MIKE Cam McGrone is still the MLB. Note however that it's too late to flip defensive ends. When Hutchinson and Paye were in this wouldn't matter—both are heavy dudes who've played plenty of Anchor and are good at keeping their Vipers clean. Luigi Vilain however is more of a specialized weakside end. He's 21 pounds smaller than Kwity, and having lost his first two seasons on campus to injury, is far behind Paye in strength development.

They've also subtly flipped the jobs of SS Daxton Hill and VIPER Michael Barrett. Barrett practices getting around crack attempts and shooting outside when a defensive end is occupying blockers from an inside gap more than any other skill. Meanwhile Hill's position coach, Bob Shoop, isn't with the program for undisclosed reasons. I can't begin to speculate what the reason is, but the result is safeties who aren't being coached on the level that they were in previous years. Daxton has been a playmaker this year, but he is also a quasi-cornerback who plays some cornerback. Wisconsin's two-TE formation and swap turned the strong safety role into literally that of an outside linebacker. That's a less familiar situation. Michael Barrett wasn't perfect at edge protection, however it's his primary role.

Wisconsin identified that Barrett wasn't the outside linebacker they wanted to attack, and Josh Ross was. Let me show you the first play after halftime:

Again, flipping the Y tight end (Jake Ferguson) flips the OLBs so Michigan can keep Barrett to Ferguson's side, and Wisconsin knows this and is motioning before a run play that attacks the Ross side. This is almost the same play except the Jet WR is a kickout blocker and the ball goes to the running back. Carlo Kemp has made an adjustment, getting outside that offensive tackle and swimming through the H-back to get a tackle attempt in the backfield. When your DT has won you rally and clean up. Ross slows up when he makes contact with the H-back, then lets the guy around him.

Gray at least came off the receiver, though his edge is wide and less than a 1-for-1. Brad Hawkins, the safety on this side who should be screaming down to help, is tied up with that receiver. It's Daxton Hill who runs this down finally.

Hill and McGrone almost made another play that drive that just need Josh Ross to pop an H-back. This Ross got a little tougher job because Taylor Upshaw got moved (and then held) but he also got a lot of old linebackers yelling about physicality when #34 shoulders him out of the play.

For what it's worth I thought Upshaw was responsible for the two reverses, since he was constantly shuffling on that backside edge.

Weakness Nerfs Playmakers

The safeties are going to come into play here but why does the DE personnel difference matter on a play that's not going to that side? Well, it's a weakness, and anticipating the way defenses respond to their weaknesses is a good way to attack them. Every team has them, to some degree. But defenses hide personnel weaknesses behind strengths so you can't get at them. Wisconsin uses a five-man front that puts OLBs on permanent edge duty; their Cover 2 safeties hammer down on intermediate zones to make you throw over them.

Michigan State uses wide fronts and hard edges, pushing the ball back inside where speed matters less than testosterone. Indiana blitzes the edges to force quick decisions into varied coverage looks that are hard to anticipate. And Michigan compensates for DTs who get pushed around by diving their linemen into the A and B gaps and trusting their linebackers to outrace any backfield material to the edges.

Anticipating how the defense will play you is a big part of getting those subtle victories in blocking. Michigan might be playing to spill with Vilain, but they'll almost certainly be doing so with Carlo Kemp, who was playing defensive tackle until both All-American DEs went out. Flipping the formation moved Michigan's best edge defender, Michael Barrett, to the backside where he can't do any harm, and got a pretty good guess about how the defense will attack them in the process. They're so sure in fact that they leave Donovan Jeter unblocked the whole play, trusting that Kemp is going B gap so Jeter will go inside to the A gap, again, behind the play.

Putting a tight end over Vilain matters also. Let's slow it down and watch the feet of the two inside linebackers, particularly those of #12 Josh Ross:

Why are they stepping backside? Well, they're reading their guards, for one. McGrone is checking the one Hinton's got, as well as the backfield. As the backside MLB in this configuration he's got to worry about the handoff, and filling aggressively if that TE and OT lined up over Vilain turn that into a double.

Ross's step is with a little shimmy by the left guard. But there's a half-beat after the guard heads to the playside edge where Ross is still watching the running back, since McGrone replacing is going to demand Ross's attention inside on an RB handoff. When Jeter goes into this A gap (unblocked), Ross has to be making Jeter good by blasting into the next gap over.

Simply put, Wisconsin's downhill running game against this defensive line put the fear of the cheese gods into Michigan's linebackers, ensuring Ross wouldn't muck up their play from behind. Let's go back to the other play I clipped—the first play of the game. Watch McGrone here because this time he's the guy who's supposed to be arriving from the backside if Green doesn't falldowngoboom.

Michigan later went back to their Minnesota configuration of playing Dax as the overhang on open (no WR) edges, so Green can take a read before reacting.

That works better but it removes Hill as a late line of defense if the offense goes the opposite direction.

Where Do We Go From Here?

The primary takeaway from Michigan's putrid edge defense this week is that they were probably terrified of getting hammered inside, and their cornerbacks are overwhelmed so much with pass pro that they're not much help in this department. Things should improve with Ross I think, at least until Ohio State—remember Michigan's linebackers fritzed out last year too. We can't fix the coaching right now, and that's what's needed to get the linebackers to still trust the defensive line when they're overmatched. The cornerbacks, well, there's a lot on their plates right now but moving Dax down on open edges is probably worth what they'll lose when Green gets matched downfield against a tight end.

Michigan's defense can't get to good this year. There are too many bad players, and not enough extraordinary ones, and not enough time to develop a new system that plays to what strengths they have. What they can do is try to get more cohesive so they don't continue to be worse than the sum of their parts. Right now Michigan has a lot of Guys who cause problems when they try to be Dudes. The good news is the first step—going from the disaster they are now to mediocre—is the easiest.