Surgery on the left knee of University of Oregon quarterback Nate Costa surgery resulted in the repair of a partially torn anterior cruciate ligament as well as repairing cartilage damage, which is expected to prevent the return of the third-year quarterback this season.

The Hilmar, Calif., signal-caller suffered his latest injury in an Aug. 20 practice after beginning fall drills atop the Ducks’ depth chart. The non-contact injury resulted in a third surgery Wednesday on a left knee that he originally injured in high school and again was repaired a year ago.

Sophomore Justin Roper will assume the starting quarterback role when Oregon opens the 2008 Saturday night vs. Washington.

GoDucks.com