TUCSON, Ariz. (AP) - Southern California went into the season with national title hopes behind a Heisman Trophy front-running quarterback.

After a mistake-filled loss to Arizona on Saturday, the Trojans will have to play well just to get into the Pac-12 championship game.

USC spoiled record-breaking days by Marqise Lee and Matt Barkley with five turnovers and 117 yards in penalties against Arizona, leading to a disheartening 39-36 loss in the desert.

Lee broke the Pac-12 record with 345 yards receiving and Barkley set the school record with 493 yards passing, but they couldn't connect on a last-second heave into the end zone.

USC, the preseason No. 1, dropped eight spots with the loss to No. 18 in the AP Top 25.