41 points. 522 yards. 307 yards rushing. 32 first downs. 89 plays.
That was not something anyone expected from this defense. Michigan went to Bloomington and gave up more yards on the ground and total than it had all season, and more points than it allowed in the first six games combined. By the end of the game Indiana gave up all pretense of passing and fed Jordan Howard over and over; from the start of Indiana's go-ahead drive in the fourth quarter until the last play of the second overtime Indiana did not pass the ball once. Howard finished the game with 238 yards.
It was a colossal beat down on the ground, and Michigan's once fearsome defensive line was ripped apart and its linebackers run past. Indiana doubled up the best rushing total allowed by Michigan's defense so far this year.
So what went wrong?
Pretty simply, Michigan got tired. But there is a little more to it than that, so let's dive in.
The Ryan Glasgow injury was troubling before this game, but now it seems to be a five alarm fire. He has been the point man for Michigan's crushing rush defense, and his presence was missed. One of the biggest advantages Michigan has had on defense this year is its ability to outwork opponents. That starts up front with a defensive line that ran a legitimate two deep at all three interior spots. Michigan's depth up front allowed the Wolverines to run out different packages, rotate players consistently to keep them fresh, which allowed everyone to thrive. This wasn't a Mike Martin/Ryan Van Bergen ironman competition like the 2011 season, but what would happen if you cloned those guys twice over and then rotated all six of those clones through. If you haven't guessed, this isn't a luxury that most teams are afforded.
Glasgow's presence on the field cut Maurice Hurst's time in half, but effectively doubled his effectiveness by allowing him to focus more energy on fewer plays. With Glasgow on the shelf, Hurst had to shoulder a larger share of the defensive load. The defensive coaches did throw Tom Strobel into the rotation at nose tackle, but Strobel is a positional vagabond and a massive step down from Glasgow.
The line is also down two other rotation players in Bryan Mone (lost before the season) and Mario Ojemudia (season ending Achilles injury), and suddenly what was the strength of the team looks to be fraying at the edges under the heavier workload. Matt Godin has also been banged up, and with Glasgow out both Willie Henry and Chris Wormley have had to play more.
This was all exacerbated by Indiana's tempo offense which eschews huddles and effectively locks opposing lineups on the field for multiple plays at a time before substitutions can happen. It is one thing to play Tom Strobel a handful of times to give Hurst a blow. It is another thing entirely when the opposing offense can dictate when you can sub him off the field thanks to its offensive philosophy.
Injuries and pace are part of the game, and this isn't an excuse as much as a preamble to what was a pretty smart coaching move by Kevin Wilson.
Early in the game it became apparent that Kevin Wilson wasn't going to play safe. He went for three fourth down conversion attempts in the first quarter. While this undoubtedly had something to do with the situations being ripe for fourth down attempts, the added benefit of this strategy was the way it set the tone for the game early.
Against a team that plays more aggressive style offense in terms of going for it, the math for successful stops changes. All the sudden stopping a third-and-five two yards short isn't as much of a victory when you know the offense is just going to turn around and run another offensive play.
Going two of three on fourth down attempts in the first quarter allowed Indiana to gas Michigan's defense early. The Hoosiers ran 35 plays in that quarter, held the ball for over 11 minutes, and while the score wasn't in Indiana's favor after 15 minutes — in part because that missed fourth down attempt led to a short-field touchdown by Michigan — the Hoosiers had done enough to set up success later on.
At halftime, the stats looked like this:
Michigan had a huge lead in yards per play as well as on the scoreboard. It looked at the time like things were going largely according to plan. Michigan's defense was giving up more yards than normal, but it was making Indiana work for those yards (just 5.5 yards per play). However, there was another way to look at the above stats, one which was a harbinger of what was coming in the second half: Indiana ran 54 offensive plays in one half. Both Oregon State and BYU ran fewer plays over the course of an entire game against Michigan. The Wolverine defense became a victim of its own success in this game: it spent the season kicking other teams off the field so quickly that it wasn't ready for a 12-round fight against someone with enough stamina for 15 rounds.
Indiana used its strengths to sap Michigan of its energy early, and while Michigan walked into halftime with an eight point lead and the first possession of the second half, the game was ripe for the taking. The punt return for a touchdown just happened to be the catalyst for what would be Indiana's strong upset bid over the second half.
And so we return to the end of the game, wherein Indiana ran the ball and ran the ball and ran the ball...and so on. That success on the ground in the fourth quarter and overtime wasn't Michigan's defense being exposed as frauds or Indiana becoming superhuman in the locker room at halftime. It was simple physiology. Michigan got tired playing Indiana at its own game.
Is Michigan's defense broken? No, probably not. But it does look to be mortal, both in terms of injuries and stamina. It remains to be seen how effective Penn State will be at exploiting these weaknesses, but the game against Ohio State looms slightly larger now.