EUGENE, Ore. -- Cal fell into an 11-point deficit at halftime, and coach Mike Montgomery felt pretty fortunate.
"We were lucky to be down 11 at the half," he said. "I hate to say that, but we were. It could have been a lot worse."
It took the Bears less than nine minutes to erase that deficit and then Cal built a double-digit lead of its own to beat Oregon 81-71 on Thursday in front of 10,487 at Matthew Knight Arena.
Cal (15-13, 8-8 Pac-10) outscored Oregon 47-26 in the second half to pass the Ducks (14-13, 7-8) in the standings.
"Coming on the road it's hard to get wins, and Oregon had the crowd going early," said Cal freshman guard Allen Crabbe, who scored 13 of his 19 points in the second half. "We came out in the second half and made a quick run and took them out of the game and then kept playing hard."
Oregon led by as many as 16 points in the first half before Cal cut the deficit to 45-34 at halftime as the Ducks shot 57.1 percent during the first 20 minutes.
"We were back on our heels in the first half, not much aggressiveness and they were taking it to us," Montgomery said. "They were getting where they wanted and as a result they made every shot because they were the aggressor and we weren't."
Oregon took a 48-38 lead on a free throw by Joevan Catron with 17:29 left in the second half. But Cal scored on seven straight possessions to cut the lead to 54-53. Jorge Gutierrez had two free throws, a steal and layup, and a 3-pointer during the stretch, and Crabbe had a free throw, layup and 3-pointer.
"I think we played harder," said Gutierrez, who led the Bears with 23 points. "As long as you play hard you get in a rhythm, and we played defense as hard as we could. We were being more aggressive."
Cal took the lead at 55-54 on a layup by Harper Kamp with 11:37 left. Oregon's last lead was 57-55 before Richard Solomon tied it and then Kamp added a free throw before Gutierrez hit a 3-pointer to put Cal ahead 61-57 with 8:21 to play.
Oregon last tied the game 65-65 on a putback basket by Teondre Williams with 4:13 left. Cal's Brandon Smith, who finished with 18 points, answered with a 3-pointer and Solomon went inside for a basket. Smith added two free throws to put Cal ahead 72-65 with 2:31 to play, and Oregon got no closer than four the rest of the way.
Cal was 15 for 24 from the field in the second half.
"The second half we played good defense, kept the ball in front of us and didn't turn the ball over," Montgomery said. "It is amazing when you are aggressive how things seem to go your way."
Tyrone Nared led the Ducks with 16 points.
Cal (15-13, 8-8 Pac-10) at Oregon State (10-16, 5-10), 3 p.m., CSNCA