Layshia Clarendon had a game-high 26 points and five assists to give No. 6 California a 73-60 win over Washington State.
Afure Jemerigbe had 14 points while Mikayla Lyles added nine points for the Golden Bears (26-2, 16-1 Pac-12), who have ripped off 14 straight wins since a loss to Stanford on Jan. 8.
With a win against Washington on Saturday, California will claim at least a share of its first Pac-12 championship.
Lia Galdeira had 18 points and seven rebounds and Mariah Cooks added 10 points and six boards for the Cougars (10-18, 6-11), who have dropped their past four games.
The game was close throughout the first half, but the Golden Bears closed the first 20 minutes with three consecutive 3-pointers, two from Jemerigbe and one from Clarendon, to take a 42-35 lead into the break.
A 9-0 run from California allowed the team to grab a 51-39 lead as Washington State failed to get a point for close to five minutes.
California's lead never fell below double-digits the rest of the way.