This time, USC was only good enough to make it close.
Once again, UCLA put forth a dominant physical performance but still gave the Trojans plenty of opportunity. USC did nothing with its late-game chances.
After the Trojans cut the lead to four, with 6:36 remaining, they went more than five minutes without scoring. O.J. Mayo travelled twice, Davon Jefferson missed a pair of free throws, and UCLA was on its way to a 56-46 victory.
"The game was there," sophomore center Taj Gibson said. "They handed the game right to us on a couple of plays. We just didn't take care of the ball."
Mayo, battling a groin injury, committed 10 of the Trojans' 22 turnovers. UCLA committed 10 turnovers as a team.
At Pauley Pavilion last month, USC stunned the Bruins, with fantastic play down the stretch from Mayo, Jefferson and Daniel Hackett. All three were absent Sunday, but Hackett was the only one who did not play. He sat on the bench, in a sport jacket and jeans, because of the stress fracture in his lower back.
Jefferson and Mayo -- the Trojans' leading scorers this season -- had four points apiece, and freshman Angelo Johnson could not replace Hackett's leadership, passing or shooting against the top team in the conference. He scored two points.
Gibson, who grabbed 12 rebounds, and Dwight Lewis were the only Trojans to score in double figures, with 16 each.
"They really guarded us tonight," USC coach Tim Floyd said. "We just didn't get enough shots up in the course of the game."
UCLA out-rebounded USC 38-31, including 19-5 offensively. The Bruins took 62 shots -- making 21 -- while the Trojans managed only 43 shots -- making 20 -- and six free throws.
Keith Wilkinson played eight minutes off the bench in place of Jefferson. USC's other four starters played the entire game. Floyd said fatigue did not seem to be a factor, because USC continued to guard well and grab defensive rebounds in the final minutes.
The turnovers proved too burdensome to overcome.
"I think I played pretty good defense on myself," Mayo said.
He declined to attribute the performance to his groin injury. When pressed as to whether he felt 100 percent, after sitting out practice Wednesday and Thursday, Mayo said, "It doesn't really matter.
"I got taped up. ... I just turned the ball over too many times. I don't think the groin had anything to do with my decision-making."
Mayo's freshman-phenom counterpart, UCLA center Kevin Love, scored 13 points, on 5-of-14 shooting, and grabbed 11 rebounds. Darren Collison led the Bruins with 14 points.
Jefferson scored 25 at UCLA on Jan. 19, leading the Trojans to the upset. He said he was not sure what the Bruins (22-3, 10-2 Pac-10) did differently this time, to limit his opportunities.
"I really don't know how they adjusted," he said, after shooting 2-of-8. "We just tried to play."
The Trojans (15-9, 6-6) find themselves in a three-way tie for fourth place in the Pac-10, with both Oregon schools on the way to Los Angeles.
Hackett does not seem likely to return, and freshman guard Marcus Simmons remains on the bench with a sprained ankle. USC did not use a perimeter sub Sunday.
"We felt we were better served with the men that were out there," Floyd said. "I like the guys that we have, and we'll try to bring effort here next week."
Jonathan Kay can be reached at Jon@USCFootball.com