Senior guard Donte Smith thought he had an open fast break layup and an opportunity to close UCLA’s eight-point lead.
Instead, Smith found himself stumbling to the ground with a little more than four minutes to go.
The Bruins’ Lazeric Jones had chased him down and cleanly rejected the shot, stuffing the ball back into Smith’s hands.
That’s the type of night it was for USC and its guards as they fell 64-50 to crosstown rival UCLA (15-7, 7-3).
Vucevic and Stepheson got no help from the guards, who made only four jump shots in the game.
The Trojans’ (12-11, 4-6) starting guards managed only seven points and USC didn’t have a single perimeter point in the final 25 minutes of play.
Just like the first crosstown showdown this season, UCLA entered on a hot streak having won five of six.
Unlike last month’s game, the Bruins guaranteed themselves a victory by jumping out to an early lead with a 12-4 run after Stepheson scored the first two points of the game.
UCLA would not trail again.
USC showed some life ending the first half on a 9-2 run, punctuated by a Maurice Jones drive and dish to Vucevic for an emphatic slam just before the first-half buzzer expired.
The run trimmed the lead down to a one-point halftime lead after the Bruins had led by as much as nine.
Joshua Smith came off the bench to lead UCLA with 15 points on 5-of-9 shooting. He also collected six rebounds.
As a team, the Bruins shot 48 percent while in the second half USC made only seven field goals, shooting 30 percent from the floor.
The Trojans have a week to lick their wounds before hosting the Oregon schools.
They will play Oregon State at the Galen Center next Thursday.