Jawanza Starling returned a fumbled snap 80 yards for a third-quarter touchdown and Matt Barkley passed for three scores Saturday night as Southern California beat Notre Dame 31-17 to end the Irish's four-game winning streak.
The Trojans (6-1) jumped out to a 17-0 lead in the first half and then fought off a comeback by the Irish (4-3) in the first night game at Notre Dame Stadium in 21 years.
USC, which has now won nine of the last 10 meetings in the long rivalry, had a 443-267 advantage in total yards.
Starling picked up the loose ball after Notre Dame backup quarterback Dayne Crist - who entered the game when starter Tommy Rees was momentarily shaken up - couldn't get the handle on a snap at the USC 1 with Notre Dame behind by a touchdown.
Crist, who lost the starter's job after the first half of the season opener, replaced Rees and completed 4 of 5 passes to help the Irish reach the 1. But when he couldn't control the snap, the ball got loose and Starling picked it up and ran in for the long TD. Instead of a potentially tied game, USC went up 24-10 late in the third.