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Saturday afternoon in Ann Arbor, beneath a green gaiter that served to maintain his poker face, Mel Tucker wouldn’t reveal whether he intentionally designed a game plan to pepper Michigan’s cornerbacks with targets deep downfield.

He didn’t need to. The proof was there for three hours Saturday. It resided outside the visiting locker room, down the white stucco hallway and on the Michigan Stadium field.

That’s where Michigan State quarterback Rocky Lombardi — fresh off a three-turnover performance against the Big Ten’s perennial doormat, Rutgers — threw for 323 yards, 196 of them to freshman receiver Ricky White, who saw a 40-fold increase in his career receiving yardage.

“We’ve got a bunch of playmakers,” Lombardi said. “You’re gonna have to cover all of them.”

On Saturday, Michigan opted for the opposite.

White was the primary benefactor, connecting with Lombardi eight times. Junior Jalen Nailor — with his 328 career receiving yards — was another, going for 68 yards. Running back Connor Heyward was there too, only catching two balls, but both for touchdowns.

At the end of it, the Wolverines’ cornerbacks could only look up at a scoreboard that read: Michigan State 27, Michigan 24, and wonder how they got there.

“Each person, we gotta look at that, every single guy, what they can do and what they can do better,” Harbaugh said when asked about the unit. “And every coach, too.”

For Michigan, the performance stood in direct contrast to everything it showed a week ago in Minneapolis. Back then, seven days and a lifetime ago, junior cornerbacks Vincent Gray and Gemon Green held the Big Ten’s reigning receiver of the year, Rashod Bateman, out of the end zone on 101 yards, most of them in garbage time.

On the first drive of the game Saturday, it looked like the Wolverines could be in for a repeat. Green, who was lauded all week for his performance as a first-time starter, forced a three-and-out with a well timed pass breakup on the left sideline.

That would be the highlight of his game.

On the next drive, Green made the mistake he carefully avoided against Minnesota, failing to turn his head in one-on-one coverage against White on a go route down the left sideline. Instead, Green only stared towards White, who streaked past him into the end zone, catching Michigan State’s first touchdown of the game.

The Spartans’ next touchdown came from the two-yard line, but it too was sparked by the deep ball. This time, it was Gray getting beat on the right sideline. Fooled by a rudimentary stop-and-go move, he stopped in his tracks at midfield as Nailor ran free under Lombardi’s 53-yard pass.

Five plays later, Michigan State was in the end zone.

“We really didn’t expect those (deep throws) because the gameplan was to hone in on the run,” sophomore safety Daxton Hill said. “But they threw some shots in there so you just have to adjust.”

So at halftime, that’s what Michigan tried to do. Defensive coordinator Don Brown dropped his safeties deeper into coverage, attempting to provide help for his outmatched cornerbacks. Midway through the third quarter, he opted for a personnel change, replacing Gray with sophomore Jalen Perry.

“We were making adjustments and they were…” Harbaugh said, letting his voice trail off with the knowledge of what came next.

What came next was a second half in which Lombardi threw for 227 yards, including 121 on downfield passes into one-on-one coverage. Perry, for his part, joined the struggles, falling over his own feet on a 31-yard completion to White at the three-yard line that all but sealed the game.

The most damning play, though, came a quarter earlier, with Lombardi backed up against his own end zone. Facing a second-and-9 with a heavy rush from Michigan and White lined up against Gray on the right sideline, he dropped back and hurled a pass 40 yards downfield, hoping his freshman could come up with it.

There was no double move or play-action. There were no suppositions about what else Michigan State might do. The Spartans were dialing up what had worked all game: Make Michigan’s cornerbacks win a battle.

And with the opportunity to shift momentum in the Wolverines’ hands, they couldn’t do it. Gray got beat, senior safety Brad Hawkins couldn’t get over in time and Michigan, for the third time in the Harbaugh era, walked off its own field with a loss to its in-state rivals.