EUGENE — Oregon junior safety Avery Patterson will miss the remainder of the season after tearing the anterior cruciate ligament in his left knee, a source has told The Oregonian.

Patterson injured his knee in the second quarter of the Ducks' 59-17 victory at Cal on Saturday. It's a significant loss to an Oregon defense reeling from injuries.

The Ducks could also be without defensive tackle Wade Keliikipi for an extended period. Keliikipi did not make the trip with the Ducks to Berkeley, and he was spotted outside of practice Monday on crutches with a large cast on his leg.

Keliikipi has been one of Oregon's most dependable defensive players the past two seasons. He started the first nine games this season, registering 20 tackles, including four for a loss.

Oregon's other starting defensive tackle, junior Taylor Hart, left Oregon's facility with a boot on his left foot Monday. His status for Saturday's game against No. 14 Stanford is unknown.

Oregon played much of the Cal game without its five top defensive linemen. In addition to injuries to Keliikipi and Hart, Dion Jordan (shoulder), Isaac Remington (ankle) Ricky Heimuli (knee) all suited up but did not play.

Patterson became the starting free safety after senior John Boyett, the Ducks' most experienced defender, opted to have season-ending knee surgery in early September.

Patterson is tied for fourth on the team with 44 tackles. He has three interceptions this season, two of which he returned for touchdowns.

Sophomore Erick Dargan is expected to start at free safety for the Ducks against Stanford.

Two of Oregon's backup cornerbacks, Troy Hill and Dior Mathis, also sat out the Cal game with unspecified injuries.

-- Adam Jude; follow on Twitter.

