Layshia Clarendon scored 22 points and No. 6 California held off a late Southern California rally to beat the Trojans 72-64 on Sunday.
After trailing by 13 points in the second half, the Trojans battled back to make it a close game. Clarendon 9 of 17 shots and added a late basket down the stretch to help close out the win.
Cassie Harberts' basket with 1:54 to play cut the lead to 63-59 but USC couldn't get any closer.
Clarendon had a three-point play and Gennifer Brandon, Avigel Cohen and Afure Jemerigbe added six free throws late to seal the win.
The Golden Bears (23-2, 13-1 Pac-12) remain tied for first-place in conference with Stanford, which defeated UCLA on Sunday.
Harberts led USC (8-17, 5-9) with 20 points and Ariya added 15 points.
Brittany Boyd scored 16 points and Jemerigbe added 11 points for the Golden Bears.