ANN ARBOR, Mich. — Even on Rivalry Saturday, some things were certain.

For one, either No. 2 Ohio State or No. 5 Michigan would effectively vanish from the College Football Playoff chase by day’s end. For another, but probably less important to the 111,156 chilled souls on hand, the sky’s hue promised that Michigan Stadium would soon resemble a snow globe.

The snowfall started before kickoff. The elimination took longer but exacted consequences that reshaped the college football season: Michigan upset Ohio State, 42-27.

It was Michigan’s first victory over Ohio State since 2011, and it secured the Wolverines a place in next Saturday’s Big Ten Conference championship game in Indianapolis.

Michigan (11-1, 8-1 Big Ten) is poised to rise into one of the playoff’s top four slots after tallying 487 yards of offense.

Just one week removed from demolishing a Michigan State team that was then ranked seventh, Ohio State (10-2, 8-1 Big Ten) will watch the sport’s biggest games from home. Such is the enormous price for a November afternoon of dropped passes, costly penalties and an offense that often looked as if its playbook had been left behind in Columbus.

Ohio State, which had been averaging almost 560 offensive yards per game, finished with 458.

Ohio State, which reached last season’s national championship game, won Saturday’s coin toss and, in a decision that seemed more pivotal in retrospect, gave Michigan the ball first.

All through the afternoon’s inaugural drive, the Wolverines could not find a clean set of downs on their first or second tries. But, faced three times with third downs, they turned each time to Hassan Haskins, a senior tailback from St. Louis. Third-and-2? There was Haskins with a 16-yard gain. Third-and-1? Just a pair of yards, but enough. Third-and-1 again? Haskins for 17. With a chance to score on first down, Michigan opted to send A.J. Henning sweeping toward the sideline and then toward the goal line for a touchdown.

Then the nation’s best offense took the field. It did not look the part. The Buckeyes, askew after a bobbled fair catch seemed to have positioned them closer to the grandstands than to their own bench, went three-and-out. They had picked up just one yard, after C.J. Stroud fumbled a premature snap and fell forward onto the ball.

Soon enough, the Wolverines stood on Ohio State’s 39-yard line. Cade McNamara lofted a pass to Roman Wilson to gain 24. A two-score lead appeared imminent, and Michigan entrusted that prospect to McNamara’s gilded arm. The ball rocketed toward the end zone, but Bryson Shaw, a sophomore safety for Ohio State, found it first.

Shaw delivered the ball to his own 22, a far finer place than Ohio State had started from when it last had possession. The Buckeyes began another northward march, toward Michigan’s student section and its band and almost too many maize-shaded pompoms to fathom, much less count.

For eight plays, they diced up the Michigan defense: a series of rushes that gobbled up 56 yards, short passes that added up to 19. The sputtering started when, on second down with their own goal line just three yards away, a pass to Chris Olave went incomplete.

The stadium — and if you do not at least fleetingly buy into the notion of home field advantage, test your hypothesis in Ann Arbor some Saturday — thundered and roared and hollered and menaced on third down, forcing a false start.

And then Aidan Hutchinson, who started the day with a share of the Big Ten’s lead in sacks, stormed through Ohio State’s line to send Stroud to the ground for a six-yard loss. (Later in the day, he picked up his 13th of the year, a single-season record for Michigan, which is in its 142nd season of varsity football.) The prospect for a tied score dimmed, replaced by the Buckeyes’ hopes for a 31-yard field goal, which they made.

In the second quarter, though, Stroud and his receivers bubbled up as advertised. Over 99 seconds, Ohio State ran four plays, three of them through the air. The Buckeyes collected 56 yards, none more athletically artistic than the last 25, when Garrett Wilson, aloft a few feet outside of the end zone, caught Stroud’s pass. He pushed off with his left foot, seizing just enough power from the home team’s turf to cross the goal line. It had taken more than 19 minutes, but Ohio State, at last, had the lead.

It was gone about five minutes later, when Haskins took his turn going aloft in search of a score, tumbled atop and across a pile of defenders for a score.

After all of that, Michigan held the narrowest of edges, 14-13, at halftime.

Ohio State’s first effort after the intermission fizzled. Michigan’s did not.

Blake Corum, a sophomore running back, had just rushed for 13 yards, to the Michigan 32, when he took a handoff. He raced left, and as he approached the Michigan logo at midfield, cut across the turf. Defenders scampered — five of them were in pursuit as Corum neared Ohio State’s 25 — before Ronnie Hickman caught up with him after 55 yards.

Haskins, on the next play, ran 13 yards for a touchdown that helped push the score to 21-13.

On Michigan’s next possession, Haskins, his team invigorated after an unsportsmanlike conduct call against Ohio State that shuttled the Wolverines to the 1-yard line, capped a five-play drive with another touchdown run.

Ohio State whittled the gap early in the fourth quarter.

Stroud, a redshirt freshman who arrived in Ann Arbor as a contender for the Heisman Trophy, took charge from the start of a drive that began in the third, with a 12-yard pass to Olave, one of Ohio State’s sensational receivers. A Hutchinson sack knocked him off-balance briefly, and two plays later on third-and-19 he connected with Jaxon Smith-Njigba for 26 yards.

After 17 plays, the last a rush for a single yard, Ohio State was within a score of a knotted ballgame.

But like almost every good thing for Ohio State on Saturday, the suspense and the ambition were soon complicated. Although a pass interference penalty against the Buckeyes proved the most lucrative element of the next Michigan drive, the Wolverines had Haskins in the end zone again within five minutes.

Dented but not yet done, Ohio State stitched together a drive that, had the Buckeyes won, would have been a prized sequence of fortitude and daring. Twice faced with fourth downs, Stroud kept Ohio State’s aims alive with a pair of passes, including one to TreVeyon Henderson, whose arrival in the end zone, with a successful extra point afterward, led the scoreboard to read 35-27 with 4:45 to play.

The snow had largely stopped falling by then. What had settled earlier on the artificial turf had melted. The seconds ticked and ticked and ticked away as Haskins ran and ran and ran.

The snow picked up again. Haskins, of course, ran some more.

He scored another rushing touchdown, his fifth of the day, and tied Michigan’s game record.

It was soon clear it would not matter. Michigan, for the first time in a long while, had already been too much.