Urban Meyer says he can't believe he let someone on his own sideline injure J.T. Barrett, and he is going to find out who it was. (0:50)

Ohio State quarterback J.T. Barrett aggravated a knee injury Saturday when he was bumped on the sideline by what coach Urban Meyer called "a guy with a camera."

Barrett said he was warming up in a tight space behind the team bench prior to Ohio State's first drive of the game against Michigan when someone tried to squeeze past him. The person bumped his knee as he was throwing a pass.

The quarterback said he didn't think the contact was intentional but that the small collision twisted his leg and aggravated a knee issue he has been dealing with for most of the season. Barrett played until midway through the third quarter of the 31-20 win even though the leg stayed "locked up" throughout the game.

"It just twisted up on me, and I wasn't able to pop it out again," Barrett said. "... I remember he was wearing something gray, and he just kept walking. I'm pretty sure he got a little nervous."

Ohio State coach Urban Meyer said during his postgame news conference that he will launch an "all-out investigation" to find out who caused the injury. He said he was too angry after the game to go into much detail about what happened to Barrett.

"I'm just so upset with myself. It's a non-football injury. Too many damn people on the sideline, and a guy with a camera hit him in the knee," Meyer said. "I'm going to find out who. ... Someone on your friggin' sideline hurts your quarterback. I'll find out who it was."

The pregame collision kept Barrett from finishing Saturday's game, but he said he thinks he will be healthy enough to play in the Big Ten championship game next Saturday against Wisconsin.

Meyer said he didn't know Barrett's status for the title game. The ninth-ranked Buckeyes (10-2) could play their way into the College Football Playoff discussion by beating the fifth-ranked Badgers in Indianapolis.

Barrett threw for one touchdown and ran for another before leaving the game after being tackled awkwardly by a pair of Michigan defenders. Barrett needed help from athletic trainers to get up, jogged from the field to Ohio State's locker room and did not return to the game.

He returned from the locker room in the fourth quarter but remained on the sideline. Barrett finished with 15 carries for 67 yards while completing 3 of 8 passes for 30 yards.

Redshirt freshman Dwayne Haskins replaced Barrett and helped lead a comeback victory in his first action against rival Michigan. Haskins entered the game with Ohio State trailing 20-14 and led back-to-back scoring drives.

Haskins completed 6 of 7 passes for 94 yards. He also ran for 24 yards, 22 of which came on a third-down scramble that set up a touchdown on the next play.

Ohio State players said they have confidence in Haskins to lead them against Wisconsin if Barrett isn't healthy enough to play.

Barrett missed the Big Ten title game three years ago after breaking his ankle in the 2014 season finale against Michigan. Cardale Jones replaced Barrett that year and carried Ohio State to a national championship.

Now a senior, Barrett said he doesn't think he will need an understudy to step in for him this time around.