LOS ANGELES (AP) - Dennis Dixon had a tough night in Los Angeles.

He finished with 15 completions in 23 attempts for 130 yards and ran for 24 yards in Oregon's demoralizing 35-10 loss to the USC Trojans Saturday. But more than that, he was simply off. He threw an interception and a pitch to Jonathan Stewart became a fumble.

On top of that, he got knocked around, and finally left in the third quarter when he got hit in the head.

Dixon was replaced by Brady Leaf, who completed 13 of 22 passes for 104 yards and a touchdown.

The Trojans (8-1, 6-1 Pac-10) extended their winning streak at the Los Angeles Coliseum to 31 games. Coach Pete Carroll's teams are 18-0 in November since he became USC's coach in 2001.

With the victory and four losses among top 10 teams, USC moved from No. 7 to No. 4 in the AP Top 25. Oregon, No. 21 heading into the game, dropped from the rankings.

USC's John David Booty completed 16 of 25 passes for 176 yards and one touchdown with one interception. Steve Smith caught seven passes for 88 yards, and Dwayne Jarrett made six receptions for 54 yards and one TD.

Turnovers deep in Ducks territory led to USC's second and third touchdowns, and Oregon (7-3, 4-3) didn't resemble the team that averaged 36.3 points per game in its previous nine games.

Stewart was held to 42 yards on 14 carries.

Chauncey Washington, who carried 15 times, scored on runs of 3 and 43 yards late in the third quarter to give USC a 28-3 lead.

Leaf threw a 7-yard touchdown pass to Stewart early in the fourth quarter on fourth-and-goal. The play was reviewed twice - first being reversed because Stewart stepped out of bounds before making the catch, then being upheld because the pass was deflected by a USC player.

The Trojans responded by moving 80 yards on five plays, scoring on a 12-yard pass from Booty to Jarrett to complete the scoring.

USC went ahead for good by scoring twice early in the second quarter for a 14-0 lead.

Freshman C.J. Gable's 2-yard run capped an 80-yard drive, and Taylor Mays, another freshman, intercepted a pass by Dixon and returned it 38 yards to the Oregon 7-yard line on the first play following the kickoff. Washington scored two plays later on a 5-yard run.

Oregon moved deep into USC territory again on its first possession of the third quarter, but had to settle for a 22-yard field goal by Martinez.

The game, played before a sellout crowd of 92,000, was Oregon's first at the Coliseum since the 2000 season, when they won a 28-17 decision during Paul Hackett's last season as USC's coach. The Trojans, who went 19-18 in Hackett's three years, are 62-11 since Carroll took over.