Matt Barkley threw for three touchdowns and USC rolled to a 50-16 victory over Washington State in the Pac-10 opener for both teams Saturday in Pullman, Wash.

Stanley Havili ran for a 59-yard touchdown and caught a 22-yard touchdown pass from backup Mitch Mustain as the Trojans (4-0) won their eighth consecutive game over the Cougars (1-2), who have lost 12 in a row to BCS schools. Havili finished with 107 yards receiving on five catches and 80 yards rushing on just four carries.

Barkley was 16 of 25 for 290 yards passing. He threw an 11-yard touchdown pass to Robert Woods and 7-yard touchdown receptions to Brice Butler and Ronald Johnson.

With USC leading 21-7, Washington State quarterback Jeff Tuel threw a 6-yard touchdown pass to Jared Karstetter, closing the lead to 21-13.

That's as close as the Cougars got as the Trojans reeled off 28 unanswered points.

Karstetter also caught a 30-yard touchdown pass in the first quarter.

The Trojans are not eligible for the Pac-10 title because of major sanctions handed down this summer by the NCAA.