Maarty Leunen added 18 points and 11 rebounds for his Pacific-10 Conference leading 10th double-double of the season. The Ducks (11-4, 2-1 Pac-10) have won back-to-back games for the first time since early December.
Oregon (83.4) and Cal (80.5) entered as the top scoring teams in the Pac-10, but both struggled to find an offensive rhythm in the first half.
Oregon made few attempts at getting to the basket, preferring to take their chances with long-range attempts. The strategy worked to a degree, as the Ducks led 31-26 at halftime.
California shot 35 percent in the first half and went almost six minutes without scoring after Jerome Randle hit a 3-pointer to cut the Bears deficit to 21-20 with 9:22 left in the half.
Oregon failed to take full advantage during Cal's cold stretch, only putting together a 6-0 run before a layup by Harper Kemp ended Cal's scoreless streak with 3:29 left in the half.
Three-pointers by Kamyron Brown and Hairston put Oregon up 39-28 early in the second half, and another 3 by Hairston followed by a layup from Frantz Dorsainvil put the Ducks up 48-34 by the 14:31 mark.
But Christopher answered with 3-pointers on consecutive possessions cut Oregon's lead to 48-40. He later capped an 11-0 run with five straight points to give the Bears their first lead of the game, 56-54, with 7:18 to play.
Leunen hit a 3-pointer at the other end to spark an Oregon run that put the Ducks back up 64-56 with 5:05 left. Christopher again got Cal close; his fifth 3-pointer of the night trimmed Oregon's lead to 66-64.
But Brown followed with a pair of free throws for the Ducks, and after Hairston blocked an attempt by Anderson, he followed at the other end with a 3 to make it 71-64 with 1:57 to play.
The Ducks shot 47 percent for the game. They made 15-of-20 shots from inside the 3-point line, but just 9-of-31 from outside it.