Michigan did not score in the second half against Rutgers on Saturday. Julia Schachinger/Daily. Buy this photo.

A week ago, there wasn’t much to be concerned about with Michigan’s offense. 

Through their first three games, the 14th-ranked Wolverines averaged 47 points and an FBS-leading 350 rushing yards per game. The offensive line imposed its will on all three opponents, and sophomore running back Blake Corum had established himself as one of the best rushers in college football (albeit against weak competition). Though junior quarterback Cade McNamara hadn’t been called on much, he was effective when needed and even made a couple highlight-reel throws. 

But after a scoreless second half nearly led to an implosion in Saturday’s 20-13 win over Rutgers, the questions started to resurface. 

“There was a lot that we would have liked to accomplish more in the second half there — points, drives,” Michigan coach Jim Harbaugh told reporters Monday. “Thought we were close to doing that but didn’t get that done.”

“Didn’t get it done” is an understatement. After a 20-point first half, the Wolverines opened the second half with four straight three-and-outs. They didn’t pick up a single first down until just over five minutes remained in the fourth quarter — on a drive that later stalled and ended with a missed field goal. The same offense that averaged 7.1 yards per carry in the first three games notched just 42 total yards in the second half. 

Even more, those shambolic numbers weren’t the result of an injury, or an unforeseeable tactical change from Rutgers coach Greg Schiano (if such a thing exists). Really, the shift was simple: The Scarlet Knights stacked the box, and Michigan insisted on running into it. 

Harbaugh has been quick to dismiss any questions about the Wolverines “falling in love with their stuff,” but it’s hard to describe Saturday’s playcalling any other way. Michigan’s offensive linemen are good — far better than anyone expected entering this season — but the coaches designed plays that could only work if they executed every block perfectly. They did not. 

That brings up the critical question of the season: The offense has the personnel to score points. But does it have the coaching?

Saturday’s issues, of course, didn’t stop with the run game. McNamara was solid in the first half, completing 8-of-11 passes for 156 yards, a good chunk of which came on a pair of long completions on the second touchdown drive of the game. In the second half, though, he was a poor 1-for-5 for seven yards — including a brutal three-and-out when he missed two open receivers and junior receiver Mike Sainristil dropped a slightly low ball. With so little opportunity for McNamara to show off his arm thus far, it’s difficult to evaluate exactly what the offense can expect him to achieve this season.

But here’s the thing: Playcalling is not a binary decision between whether to run or pass. For the Wolverines on Saturday, it seemed to be. 

Once Rutgers started stacking the box, Michigan’s playcalls remained stale and uncreative. When it wasn’t running into the teeth of the defense, it was mostly relying on straight pass plays — no RPOs, no play actions or screens to take advantage of the over-aggressive defense. McNamara wasn’t perfect, but he shouldn’t be put in situations where he’s expected to be. 

The run plays, too, lacked imagination. The staff didn’t rush Corum around the edge where his athleticism would be most valuable, nor did it use — or even threaten to use — sophomore receiver A.J. Henning on an end around. In fact, despite Henning being possibly the most explosive player in an offense stacked with them, he didn’t touch the ball outside of punt returns. 

Early in the third quarter, when Michigan boasted a 20-3 lead and all the momentum, it was almost understandable for the coaches to take a more measured approach, but even then, running the ball on 3rd-and-12 in plus territory is confusing in basically any scenario. It’s downright baffling when facing an opponent that’s less athletic at every skill position — especially since the sense of urgency didn’t return when the Scarlet Knights started to crawl back into the game. 

“Looking back, I think it was just a lack of momentum,” McNamara said Monday. “I think we just couldn’t really get something going there in the second half — pass game or run game. We were seeing a couple different things, but overall, just a lack of momentum.”

When Michigan travels to Wisconsin this weekend, it’ll go up against the current top run defense in college football. On 68 rushes faced, the Badgers have given up 69 rushing yards — including just three (!) against Notre Dame on Saturday. The Wolverines won’t succeed running straight inside zone all game. 

Luckily for them, though, a possible solution is already there. In the first three games, the offensive line paved holes for Corum running power and pin-and-pull — two longtime staples of the Harbaugh offense. Especially if Michigan can find some success in the air, combining those concepts with attacks on the edge should open things up again for the backs. 

But if the playcalling stays simple and predictable — and if the Wolverines climb back into their shell at the first sign of adversity — that spells trouble for this weekend and beyond. 

Senior Sports Editor Brendan Roose can be reached at rooseb@umich.edu or on Twitter @BrendanRoose.