Jabari Bird scored 15 of his 20 points after halftime, when Cal (21-14) had to overcome a seven-point deficit. Justin Cobbs had 18 points and David Kravish 12.
Askia Booker scored 17 points, Xavier Talton added 13 and Colorado held off California 59-56 in the quarterfinals of the Pac-12 tournament on Thursday.
It was a costly loss for the Golden Bears, who began the final week of regular-season play tied for fourth place in the Pac-12 with Colorado and Stanford.
Cal (18-10, 9-6), struggled at times against Arizona’s defensive pressure and had little chance of stopping the Wildcats at the other end to lose for the 17th time in 19 games at McKale Center.
Justin Cobbs scored 22 points, 15 in the second half and seven in overtime, as California held off Washington State’s 3-point barrage, 80-76 on Wednesday night.
Dwight Powell had his third double-double in five games and Anthony Brown scored 11 points in the final 10 minutes to help Stanford beat California 80-69 on Wednesday night.
Jahii Carson scored 11 points in overtime and Arizona State got another big game out of transfer Jermaine Marshall to help the Sun Devils beat California 89-78 on Wednesday.
Justin Cobbs scored 22 points and Jordan Mathews added 18 for the Golden Bears (14-5, 5-1). The loss left idle No. 1 Arizona as the league’s only undefeated team. The Bears had their six-game overall winning streak snapped and their four-game streak against USC ended.
Tyrone Wallace scored 14 points with eight rebounds as California stayed unbeaten in the Pac-12 with an 82-56 win over Washington on Wednesday night.
Devin Oliver had 21 points and Dayton halted an early second-half surge by California to win 82-64 in the Maui Invitational on Wednesday.