Ohio State may not have Nick Bosa against Penn State on Sept. 29.

Buckeyes coach Urban Meyer said at his news conference Thursday that the star defensive end had surgery on what the team is calling a core muscle injury and is out indefinitely. Ohio State plays Tulane on Saturday before prepping for the Nittany Lions.

Bosa was injured rushing the passer in the first half of Ohio State’s 40-28 win over TCU in Week 3. He immediately left the field following the play and went to the locker room. He watched the second half of the game out of uniform from the Ohio State sideline.

Bosa leads team in tackles

Bosa entered the season as a preseason All-American and was playing like one through the first few weeks of the season. Before the injury he forced a fumble in the end zone that Ohio State recovered for a touchdown. He scored a touchdown in Week 1 vs. Oregon State and leads the Buckeyes with 14 tackles. Six of them have gone for loss and he has four sacks.

The good news for Ohio State is that the Buckeyes have one of the deepest defensive lines in the country. The bad news is that Bosa may be the best defensive lineman in the country. He’s hard to replace. Especially if he’ll miss significant time and be unable to play against OSU’s Big Ten East rivals.

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Nick Bromberg is a writer for Yahoo Sports.

Follow @NickBromberg on Twitter

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