Ohio State was in the midst of jeopardizing what has been a nearly flawless season on Saturday.

A 21-0 lead over Penn State was melting away because of fumbles. During a replay review on one of them, coach Ryan Day gathered his team.

“I brought the team together — offense and defense together,” Day said. “Typically, you don't have an opportunity to do that in the game. I said ’We talked about going into a big, heavyweight match, and you're going to take shots. And one of the things about playing in a game like this is, you have to be willing to take punches, and you have to not flinch when it happens.’”

The No. 2 Buckeyes did regain their footing, and they held on for a 28-17 victory over the No. 8 Nittany Lions on Senior Day at Ohio Stadium. The win clinched the Big Ten East title and a spot in the conference championship game.

But it was also an eye-opener heading into next week’s game at their arch-rival, a resurgent Michigan team. The Buckeyes (11-0, 8-0 Big Ten) had won by an average of 42 points this season, and their smallest margin of victory was 24.

Early in Saturday’s game, it looked like this would be another rout. On its first possession, Ohio State drove 91 yards, all on the ground, against a Penn State defense that had allowed the fewest yards per carry — 2.19 — in the country.

For a fleeting moment, the Buckeyes appeared on the next drive to have taken a 14-0 lead when officials signaled a touchdown on a Justin Fields keeper. But Penn State had jarred the ball loose before Fields crossed the goal line, as replay review showed, and Penn State took possession.

It was a sign of things to come. However, the Buckeyes scored later in the quarter and took a 14-0 lead into halftime, then drove 75 yards for a touchdown on the first possession of the third quarter. At that point, Ohio State had outgained Penn State 330-64 as the Buckeyes defense dominated, bolstered by the return from suspension of defensive end Chase Young.

When quarterback Sean Clifford was injured on the Nittany Lions’ ensuing drive, Penn State looked doomed. Instead, backup Will Levis gave his team a jolt with his running, and the Nittany Lions scored to make it 21-7.

It got worse, quickly. J.K. Dobbins, who finished with 157 yards on 36 carries, fumbled on Ohio State’s next play. Penn State quickly scored to make it 21-14.

Then Fields fumbled. It was during the replay review of that play that Day talked to his team. Penn State got the ball at the Ohio State 35 and moved to the 11 before a false-start penalty and a sack by Young and Jashon Cornell forced Penn State to settle for a field goal.

Penn State got no closer. The Buckeyes stuffed the Nittany Lions on their next possession and took over at the PSU 44. Five plays later, Fields threw a 28-yard touchdown pass to Chris Olave, who caught the ball in traffic to push the lead to 11. It was as if the entire stadium exhaled.

Linebacker Justin Hilliard then ended a Penn State drive with an interception at the Ohio State 20 with 10 minutes left in the game.

Penn State didn’t seriously threaten again. Cornerback Shaun Wade broke up a fourth-down pass from the Nittany Lions’ 32 with 3 minutes left.

“We were pushed, but we made a lot of mistakes, and it was on us,” Dobbins said. “Credit to them. They did a good job. But we messed up a lot.”

Now their arch-rival awaits, with the postseason that the Buckeyes expect to include the College Football Playoff after that. Day said he “absolutely” believes that the Buckeyes will be better in the long run for surviving Saturday’s struggles.

“To win a game like that that was not clean shows the toughness that we have, because you walk out of that game thinking, ‘Oh, we probably could have won a lot bigger than that,’” Day said.

“Penn State's a great team. They did a really good job. But we've got to take care of the ball. I said it to one of the coaches, ‘Maybe it's been a little too easy at times.’ This was hard today. We learned some lessons, and hopefully we can go from there.”

brabinowitz@dispatch.com

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