USC Trojans offensive lineman Toa Lobendahn will miss the rest of the season with a torn ACL, interim coach Clay Helton announced Sunday.
The injury occurred in the first half of USC's 42-24 win over Utah on Saturday.
Lobendahn started the season at right guard, but switched to center during the Trojans' loss to Washington on Oct. 8 when Max Tuerk also suffered a torn ACL.
With Lobendahn out, USC will turn to sophomore Khaliel Rodgers at center. Rodgers started three games at left guard in 2014.
Freshman safety Marvell Tell will be out at least six weeks with a broken clavicle.
USC (4-3, 2-2 Pac-12) plays at Cal (5-2, 2-2) on Saturday.