BLOOMINGTON, Ind. — Ohio State quarterback Julian Sayin will miss “several weeks” with an injury to his throwing shoulder, coach Ryan Day said Saturday.

Sayin injured the shoulder during the fourth quarter of Ohio State’s 19-15 victory at No. 5 Indiana.

True freshman Luke Fahey replaced Sayin and will remain the Buckeyes’ starting quarterback during Sayin’s absence.

Ohio State has a bye next weekend before traveling to No. 19 USC on Oct. 31.

“We’ll regroup,” Day said. “We’ve got a good team. When Luke’s in there, we just may need to do things just a little bit differently, but the bye week gives us a chance to regroup on that and put our heads together.”

Sayin suffered the injury when Indiana’s Mario Landino hit his right shoulder while sacking him and forcing a fumble in the fourth quarter. Sayin later emerged from the locker room with his arm in a sling. Day said he didn’t immediately have any further details on specifics of Sayin’s injury.

Sayin was a Heisman finalist last year in his first season as the starter.

This year, he’s completing 71.2% of his passes for 1,772 yards. He also has thrown 17 touchdowns with just two interceptions.

Sayin threw two touchdown passes Saturday, including a 38-yarder to Jeremiah Smith on fourth-and-1 early in the fourth quarter that gave the Buckeyes a 19-7 lead.

“We wish Julian a speedy recovery,” said Smith, who now has 39 career touchdown receptions, tying former Michigan wideout Braylon Edwards for the most in Big Ten history. “But next man up. Fahey did a great job today. … I think he did everything in the right way. Handled the pressure very well.”

Fahey, a 5-foot-11, 206-pound three-star recruit out of Mission Viejo, California, beat out sophomore Tavien St. Clair for the backup job during the preseason.

“He’s got confidence, he’s got athletic ability, he’s a competitive kid,” Day said of Fahey. “I don’t think the moment was too big for him.”

On his first snap Saturday, facing second-and-28 after Sayin’s fumble, Fahey scrambled for 8 yards before drawing a late-hit penalty on Indiana that gave the Buckeyes a first down.

Fahey went 0-for-2 passing, and Ohio State failed to pick up another first down.

But the fifth-ranked Buckeyes held on after a fourth-down catch by Indiana’s Nick Marsh was ruled out of bounds in the end zone with just over a minute remaining.

“We wouldn’t have Fahey out there if we didn’t have full trust in him,” said senior guard Luke Montgomery. “Whatever happens with Julian, it’s next man up. … it’s Fahey’s time right now.”