LOS ANGELES (Ticker) -- California was not about to suffer the same fate as the other high seeds in the Pac-10 tournament.
Freshman Richard Midgley scored 12 points to lead a balanced attack as the 23rd-ranked Golden Bears dominated the second half en route to a 69-46 triumph over Oregon State in the quarterfinals.
Three of the top four seeds in the tournament fell on Thursday, including top-ranked Arizona and No. 14 Stanford. After a sluggish first half and indications that it could be the next upset victim, California (21-7) turned in the most dominant performance of the day.
The Golden Bears had a 33-31 lead early in the second half before exploding with a 20-3 run. Midgley buried three 3-pointers during the decisive burst and Brian Wethers capped it with a basket for a 53-34 cushion with 6:44 remaining.
"We were a little more patient in the second half," California coach Ben Braun said. "At the same time, we kept up our defensive intensity and I thought that was a big key. That was one of our better defensive efforts."
Oregon State missed 13 consecutive shots from the field and went scoreless for more than 10 minutes while California took control. Philip Ricci finally ended the drought on a dunk with 5:49 to go - the Beavers' first points since the 16:54 mark.
The Bears extended their winning streak over the Beavers to 11 games and advanced to the semifinals for the second straight season. They will face Southern California on Friday.
"It's going to be a tough game," Midgley said. "We are going to have to be a lot better offensively tomorrow."
Wethers scored 11 points on 5-of-13 for California, which shot just 43 percent (29-of-68) from the floor and made only 5-of-11 free throws.
Leading scorer Joe Shipp was limited to 10 points and 10 rebounds and Amit Tamir added nine and 10 as the Bears held a commanding 51-41 rebounding advantage.
Brian Jackson scored 12 points and was the only player in double figures for Oregon State (13-15), which lost eight of its last 10 games.
The Beavers shot just 27 percent (18-of-66) from the floor, including 4-of-24 from 3-point range.
"We did a really good job in the first half, but it's clear that you win ball games by putting the ball in the hole in the basket and we struggled with that," Oregon State coach Jay John said.
"We just couldn't knock down any buckets," said Beavers guard Jimmie Haywood, who made just 1-of-7 shots. "By them scoring and us not scoring, the lead just kept getting bigger and bigger. We had open shots, and they were good looks, but we weren't knocking anything down."
Ricci, who is Oregon State's leading scorer and was named to the All-Pac-10 team, was held to just seven points.
"We tried to limit Ricci's touches," Tamir said. "We tried to make his life as hard as possible."
The Beavers had a 20-15 lead before the Bears closed the first half with a 10-3 run. Midgley buried a 3-pointer with 2:46 to go and Tamir followed his own miss with 33 seconds left to give California the lead for good at 25-23 heading into halftime.