Barner shattered LaMichael James' previous school record of 295 rushing yards in a single game on 38 carries for the Ducks (9-0, 6-0 Pac-12), who kept their undefeated status intact.
Marcus Mariota racked up 304 aerial yards and four touchdowns, while Josh Huff made six grabs for 124 yards and two TDs as Oregon maintained its one-game lead over Stanford in the Pac-10's North Division.
The Trojans (6-3, 4-3) dropped their second straight despite 484 yards and five touchdowns from Matt Barkley, who also picked off twice on 35-of-54 passing.
Marqise Lee led USC receivers with 12 catches for 157 yards and two scores.
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