Cal's perfect Pac-12 start came to a crashing end against the conference's only winless team Wednesday night.

A half-step slow all night, the Golden Bears fell out of first place in the Pac-12 standings after a 77-69 loss to USC.

"They beat us in every phase of the game," Cal coach Mike Montgomery said.

Cal (14-5, 5-1) entered the night alongside No. 1 Arizona in the Pac-12's penthouse, two games ahead of everyone else. That comfortable cushion is now halved, thanks to an inspired performance by the Trojans (10-9, 1-5), who hadn't been closer than 18 points in their previous five conference games.

"Not to take anything away from them," Cal senior guard Justin Cobbs said, "but I obviously think we're a better team than they are."

Not on Wednesday night at the Galen Center.

The Bears were on their heels from the start, outworked and outplayed. They never led and were never even after the opening 21/2 minutes. USC was in control, leading by 13 with barely 3 minutes left.

"We got pretty self-satisfied with ourselves," Montgomery said of his team's attitude after a 5-0 conference start. "Kids didn't recognize why we won some games.

"The interesting thing about it is the people SC has lost to, we have not played yet. We've got all those people ahead of us."

Starting Sunday at UCLA, which beat the Trojans by 34 points earlier this month.

Montgomery wasn't willing to suggest the Bears were looking ahead to the Bruins, but said his team failed to execute in the fashion that led to road wins over Stanford, Oregon and Oregon State.

"It makes it really hard to defend when they're just blowing by you at the point of attack," Montgomery said. "Defensively, we were abysmal."

The Trojans scored 20 times on drives to the basket or layups or dunks, and held a 44-26 edge in interior points. "They just killed us in the paint," Montgomery said.

USC's size gave the Bears trouble in an area where they typically excel. The Trojans forged a 37-33 rebounding edge, and Nikola Jovanovic, a 6-foot-10 freshman from Serbia, scored a career-high 23 points on 8-for-10 shooting and 7 for 7 from the free-throw line.

"We just came out with no energy," Cobbs said. "They got whatever they wanted, drop-offs, layups."