The fifth-seeded Bruins (19-13) advanced to a quarterfinal game Thursday at Staples Center against fourth-seeded Arizona, which got a first-round bye. The teams split in the regular season.
Travis Wear scored 12 points and twin brother David had 10 rebounds as the Bruins completed a season sweep of the hapless Trojans, who lost their season-high 10th in a row.
UCLA big man Joshua Smith didn't play in the first half at the decision of coach Ben Howland. He finished with five points and zero rebounds after picking up three fouls in less than a minute.
USC (6-26) finished with a school-record number of losses. The 12th-seeded Trojans were led by freshman Byron Wesley with 13 points and Garrett Jackson with 11.