USC overwhelmed the Golden Bears (3-3, 1-2) from the opening drive. The Trojans held Cal scoreless until late in the third quarter, and the offense racked up 372 of its 589 total yards in the first half.

Kevin Riley passed for 193 yards and threw two interceptions in the Bears' seventh straight loss to USC. Cal hasn't won at the Los Angeles Memorial Coliseum in a decade.

David Ausberry also caught a TD pass for USC, which hadn't lost back-to-back games since early in 2001, former coach Pete Carroll's first season. The Trojans' dominant performance brightened a gloomy, gray day at the Coliseum, where USC had lost three of its past five games after a 47-1 stretch.

Shane Vereen and Keenan Allen caught late TD passes for the Golden Bears, who led the Pac-10 in several defensive categories before USC ran them through a shredder.

Barkley's scoring throw to Johnson with 8 seconds left in the first half tied USC's single-game record for TD passes, a mark he already shared with Rodney Peete, Carson Palmer, Matt Leinart and Mark Sanchez, who also did it in one half of play in 2008.

Barkley, who went 25-for-37 without an interception, had five TD passes last month against Hawaii.

Woods had seven catches for 116 yards in the freshman's second straight outstanding game.

Although the Trojans' offense was nearly flawless in the first half, their defense's performance was even more heartening. USC came into the game ranked 100th in the FBS after giving up 69 points in its past two games, but Cal was completely stifled by the Trojans until Vereen scored on a 31-yard screen pass late in the third quarter to avoid a shutout.

Blowout losses are sadly familiar to Cal fans during the mostly successful tenure of coach Jeff Tedford. Last year alone, the Bears were routed by USC (30-3), Oregon (42-3) and Washington (42-10) during an eight-win season.

USC moved 56 yards for a score on its opening drive, with Woods keeping his feet in the end zone while diving to catch Barkley's perfectly placed 16-yard throw. Ausberry finished another drive by tightroping the USC sideline and reaching over a defender to haul in a 22-yard TD pass.

Tyler rushed for an 11-yard score early in the second quarter, putting USC ahead 21-0 before Cal had even managed a first down. The Bears' offense, so fluid for much of the season, managed minus-8 yards and no first downs on its first four drives.

Woods caught a 9-yard TD pass midway through the second quarter to cap an 82-yard drive. Cal finally mounted a sustained march, but T.J. McDonald intercepted Riley's pass at the USC 5 -- and the Trojans rolled 95 yards for Johnson's first TD catch 43 seconds before halftime, converting a fourth-and-1 from the Cal 5 along the way.

Defensive tackle DaJohn Harris intercepted Riley's next pass, and USC tacked on another 26-yard drive capped by Johnson's 11-yard TD grab right before halftime.