Myles Rice had 25 points on 9-of-16 shooting from the field to lead Washington State to an 84-65 victory over Cal on Thursday at Pullman, Wash.
The Cougars (19-6, 10-4 Pac-12) have won six straight games and nine of their past 10. Washington State is a half-game behind the conference leader No. 5 Arizona, ahead of the teams' meeting on Feb. 22 in Tucson, Ariz.
The Golden Bears (10-15, 6-8) lost their second game in a row and fell to 2-9 away from Berkeley, Calif.
Washington State's Isaac Jones added 21 points on 8-of-10 shooting from the field for the Cougars. His team-high nine boards helped the Cougars win the rebounding battle 39-28.
Andrej Jakimovski had 12 points and six rebounds, Jaylen Wells also scored 12 and Rueben Chinyelu had 10 for Washington State.
The Cougars made 55 percent of their shots from the field, including 58.1 percent in the second half.
Jaylon Tyson paced Cal with 18 points. Rodney Brown Jr. finished with 12 points, and Grant Newell added 11 points. Fardaws Aimaq had 11 rebounds, but he managed just six points on 1-of-7 shooting from the floor.
Cal led only briefly after Tyson opened the game's scoring by sinking a jump shot.
Washington State immediately followed with a 10-0 run over the next five minutes to establish control.
The Cougars outscored California 14-5 over the last four minutes of the first half to take a 36-24 lead into intermission.
A 10-2 run by Washington State increased the gap to 51-33 after a three-point play by Jones with 15:17 remaining.
A Tyson jumper in the lane cut Cal's deficit to 57-43, but Rice answered with a jumper and a 3-pointer on Washington State's next two possessions to give the Cougars a 19-point lead with 12:16 left.
Cal did not get closer than 17 points afterward.
Washington State outscored the Golden Bears 40-24 in the paint.
The Cougars tallied 14 assists, led by five from Kymany Houinsou.
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