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Early in the second quarter of Saturday’s game against Northwestern, J.J. McCarthy strapped on his helmet and jogged onto the field. The Michigan Stadium faithful, in particular the student section, greeted the freshman quarterback with a raucous ovation. 

On the ensuing play, junior receiver Cornelius Johnson bounced an end-around outside for a six yard gain. McCarthy clapped his hands and trotted back to the sideline, as junior quarterback Cade McNamara re-entered to replace him.

To this point, McCarthy and McNamara have co-existed admirably. McCarthy, an uber-talented 5-star prospect, has embraced his role as McNamara’s understudy and an option in specific run-packages. 

Yet the back-and-forth system seemed to reach a crucible, at least among the fanbase, at halftime, with the Wolverines clenching a 10-7 lead over the Wildcats. 

The offensive futility — two punts, a fumble at Northwestern’s 2-yard line and a stalled drive turned field goal — sparked an outcry on Twitter, fans desperate for a shake-up. Scattered groans throughout the stadium echoed the online sentiment. 

A couple hours later, with Michigan having dispatched the Wildcats, 33-7, the panic had subsided, to an extent. Winning will cure those ills. 

Throughout Saturday, the Wolverines’ offense again showed its two-faced identity. Seven games into the season, it’s become clear that this is who the offense is — a unit predicated on rushing the football and limiting mistakes with little interest in any sort of vertical passing game. No one seems inclined for any sort of seismic change, for better or for worse. 

“Offensively, I thought we really played extremely well,” Michigan coach Jim Harbaugh said after the game. “Obviously left some meat on the bone, we shot ourselves in the foot a few times. … But I thought Cade played extremely well, J.J. as well.

“There was a lot of good.” 

Entering the season, McNamara was a virtual unknown, having played just a handful of collegiate snaps and yet to last a full game under center. It remained to be seen what exactly he could add to the downfield passing game. 

By now, the book is out. McNamara is a game-manager who thrives in short yardage situations; he’s built to engineer sustained drives rather than explosive ones. Fifty-yard bombs or electric quarterback runs are mostly out of the picture. 

Michigan’s offense is at its best when it plays to McNamara’s strengths. In the first half, as the Wolverines languished, they seemed to have strayed away from what best suits them. In one first quarter sequence, McNamara overthrew consecutive deep balls. 

“I think the deep passing game, we probably forced that a little bit today,” Harbaugh conceded. “Their safeties were playing back. … Forced that a little too much with how they were playing.” 

McNamara disagreed that those attempts were forced, but he did accurately sum up Michigan’s offensive gameplan: 

“Whatever’s working, we should stick with it.” 

In the second half, Michigan rode that formula to an offensive resurgence. Entering Saturday, the Wildcats had surrendered 205.7 rushing yards per game, the worst mark in the Big Ten by over 40 yards. After halftime, the Wolverines sought to expose a vulnerable Northwestern front. 

The third quarter proved to be an apt representation of the good half of Michigan’s offense. Sophomore Blake Corum and senior Hassan Haskins, the tantalizing running back duo, combined for 114 rushing yards in the quarter alone. Although the Wolverines didn’t complete a pass, they outscored the Wildcats, 17-0. 

That’s not to say that the passing game was entirely absent — one completed pass got called back due to a penalty, and Michigan drew two penalties through the air. But it did take second fiddle. 

“The two of them, they’re both great running backs,” Harbaugh said. “There’s something about the dynamic of Hassan one play, Blake the next. The difference, they’re both great. There’s some slight differences that make them both really special and hard to defend, I would think.” 

With McNamara, Michigan’s offense is at its best when it plays through its running backs. Even with a banged-up offensive line — sophomore guard Zak Zinter and junior guard Trevor Keegan each did not start due to injury — the Wolverines racked up a whopping 294 rushing yards. 

That’s not to say that the Wolverines should simply ignore their deficiencies in other aspects of the offense, which they appear to recognize. After the game, Harbaugh lamented the red-zone execution; McNamara faulted himself for a few of the errant deep balls; Corum in part blamed the first half struggles on a variety of new Northwestern blitz packages. 

So, despite the outside clamors for a quarterback swap, the changes are likely going to reside in those areas, on more of a micro-level. 

Upon entering Saturday’s game, McCarthy officially expended his redshirt, meaning he cannot use this season to gain an extra year of eligibility. He remains a contributor — in the third quarter, he dazzled with a 23-yard and 13-yard run, each of which induced a chorus of “oohs” and “ahhs” from the crowd. 

After the 13-yard dash, he again returned to the sideline.

“Everybody on this team, they’re all on a mission,” Harbaugh said when asked to explain the decision process of playing McNamara or McCarthy. “Whatever helps us win.” 

For now, Michigan seems to believe that McNamara does that best.