Ohio State starting center Seth McLaughlin is out with an Achilles tendon injury for the critical matchup Saturday between the No. 2 Buckeyes and No. 5 Indiana.
The Alabama transfer was injured in practice Tuesday, coach Ryan Day confirmed Wednesday.
McLaughlin was the anchor of offensive line that has been patched together because of injuries to other players.
Left tackle Josh Simmons suffered a season-ending knee injury against Oregon last month. His replacement, Zen Michalski, went down in the Nebraska game.
[College Football Playoff Rankings: Oregon remains on top; BYU falls eight spots]
The Buckeyes moved left guard Donovan Jackson to tackle and put Carson Hinzman at guard in place of Jackson. Day said Hinzman will now move to center and Austin Siereveld will slot in at left guard.
Reporting by The Associated Press.
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