The injuries are piling up for UCLA quarterbacks.
Patrick Cowan, right, who was designated the starter by coach Rick Neuheisel early in spring practice, tore the anterior cruciate ligament in his left knee in practice and could be lost for the season.
Backup Ben Olson fractured the fifth metatarsal bone in his right foot and likely will have surgery to insert a screw to aid in healing. He will be out two months.
That makes junior college transfer Kevin Craft the starter for Saturday night's scrimmage at the Rose Bowl.
If Cowan is lost for the season, it could also mean the end of his college career. He has already used a redshirt season and would have to petition the NCAA for a sixth season of eligibility.
The Bruins have nonconference games against Tennessee, Brigham Young and Fresno State, meaning UCLA's 2008 season could be over before it starts.