Ohio State junior defensive end Lawrence Wilson will miss the rest of the season after tearing the ACL in his left knee during last Saturday's win against Purdue.
This marks the second consecutive year Wilson has suffered a season-ending injury. He broke his leg in the 2007 opener against Youngstown State.
"I feel terrible for Lawrence," Ohio State coach Jim Tressel said. "I feel worse for Lawrence than for us. Guys can sprain an ankle and then you don't have them in that game, but for a guy who went through a surgery a year ago to have another surgery now -- unfortunately, that's what happens in these games."
Wilson had started all seven games this season, racking up 18 tackles with a sack, an interception and a fumble recovery.
Rob Rose or Curtis Terry likely will start Saturday against No. 20 Michigan State (ABC, 3:30 p.m. ET), or Ohio State could move Cameron Heyward from defensive tackle back to defensive end.
Adam Rittenberg covers the Big Ten for ESPN.com. He can be reached at firstname.lastname@example.org.