Ohio State is heading into its bye week with serious questions at quarterback after the news came out on Tuesday that Julian Sayin will likely miss the rest of the season.

Ryan Day said Tuesday night that, while he won't put a timetable on the injury, Sayin will be 'out indefinitely' with an arm injury that he suffered against Indiana, and the Buckeyes are now putting numerous plans in place for life without him.

"We aren't going to put any timeline on his recovery, but he's out indefinitely," Ryan Day said on Monday night. " ... based on the nature of the injury, we're putting together a plan for him not being available for the regular season and him not being available for the postseason."

Those plans revolve around true freshman Luke Fahey and five-star and second-year quarterback Tavien St. Clair. While Fahey entered the game on Saturday for Ohio State after Sayin went down, he played just one full series and was 0-of-2. Now the question is whether or not he's the go-to guy moving into its next game out of the bye, and if he's the guy for the remainder of the season.

“I think going into the last few games, Luke’s been ahead of Tavien in terms of what we’ve seen,” Day said. “But now that we have a bye week, these guys are both going to get a lot of reps. And we’re going to start to put together a plan on how we’re going to move forward. We’re going to play the guy that gives us the best chance to win, and we’ll get both these guys some reps and get an idea of how these next couple of days go."

Both quarterbacks have seen limited action so far this season. Fahey is 9-of-13 for 203 yards with two touchdowns and two interceptions. St. Clair is 5-of-7 for 52 yards with one touchdown and one interception. While Day wasn't confirming Fahey would be the guy moving forward, it is evident where his head is at right now.

"Based on what we’ve seen in practice the last month, Luke was ahead of Tavien going into the (Indiana) game," Day said. "That’s why he went in first."

Regardless, St. Clair will get his chance over the next week to put together enough reps to showcase his ability to lead this offense. At the end of the day, Ryan Day knows he may have to use both at some point throughout the back half of the season.

“Now we have to kind of come up for air and put together a plan," Day said. "So we need both the guys to practice really well, prepare, and understand that we’re going to need them to win a championship ... Obviously, the story of winning the national championship here with Cardale (Jones) being the third-string quarterback. So it’s been done before, and that’s a challenge to them. But it’s also a challenge to the entire team. Everybody needs to step up and do their part and upgrade across the board."

Coming out of the bye week, Ohio State travels west to No. 16 USC before back-to-back home games against Oregon and Northwestern. Then it's one final road matchup at Nebraska before the season-finale against Michigan.

"Ultimately, it will be my decision," Day said. "But Arthur (Smith) is going to have some say in it. Billy (Fessler) is going to have some say in it. The coaches will have some say in it. You listen to the guys on defense, Matt Patricia, but also the players, the receivers, the linemen. There’s a lot that goes with it, the quarterback position."