Penn State linebacker Michael Mauti, a projected starter, tore his right anterior cruciate ligament in a Sunday scrimmage and will be out for the season, the school said in a release Monday.
Mauti will have surgery within the next three weeks.
After playing as a true freshman in 2008, Mauti was expected to challenge for a starting role in 2009. Playing defense and special teams, the 6-2, 231-pound Mauti made 26 tackles, with one minus-yardage stop and one forced fumble a year ago. He was one of three true freshman to play in every Penn State game last season.
The Nittany Lions open their season on Sept. 5 against Akron.