Oregon State returner Gerard Lawson fumbled three consecutive kickoff returns in the fourth quarter, losing two to set up Bruins touchdowns.
The Bruins (4-1, 3-0 Pac-10) got 80 yards rushing, 49 yards receiving and two TDs from Kahlil Bell. Olson, who was playing for the first time since suffering a concussion against Utah, was 14-for-25. UCLA has beaten the Beavers five straight times.
Leading 14-12, the Beavers (2-3, 0-2) fell apart in the fourth quarter.
Lawson was called for a personal foul for hitting Terrence Austin out of bounds on a punt return. Olson then hit Breazell for a 69-yard score with 9:12 in the game to give the Bruins their first lead.
Then Lawson muffed a kickoff return. Then another. Then another.
The first one led to Bell's second touchdown. Breazell caught a 30-yard TD after the next fumble. The Beavers recovered the third but a punt was blocked. Chris Markey ran in for a touchdown and it was 40-14 Bruins about seven minutes after the Beavers had the lead.
Bell fumbled away the Bruins' first two possessions and UCLA's first five drives went nowhere. Oregon State scored on a 33-yard fumble return by Al Afalava and a 1-yard TD run by Bernard to lead 14-0. But Canfield killed two Oregon State drives with interceptions and the Beaver offense never really got on track again.
The Bruin offense, which had been held to 21 total yards in the first five possessions, woke up in the second quarter, with Olson and Bell putting together back-to-back scoring drives. Both ended in field goals from Kai Forbath of 37 and 28 yards to make it 14-6 at halftime.
Reggie Carter forced Canfield to fumble at the Beavers 5, setting up Bell for a 1-yard TD dive. The two-point conversion failed.
Oregon State coach Mike Riley has never beaten UCLA. He is 0-9, including four losses when he was John Robinson's defensive coordinator at USC.