Gennifer Brandon had 22 points, including the game-tying jumper late in the fourth quarter to force overtime, and 26 rebounds as No. 7 California rallied past Southern California, 71-63, at Haas Pavilion.
Layshia Clarendon dropped in a game-high 27 points for the Golden Bears (14-2, 4-1 Pac-12), who have won two straight and eight of their last nine.
Ariya Crook paced Southern California (7-9, 4-1) with 21 points, while Cassie Harberts followed with 15 and Kate Oliver posted a double-double with 10 points and 10 rebounds as the Trojans saw their four-game win streak come to an end.
California carried a 36-31 advantage into the second half after a hard-fought opening 20 minutes that saw six lead changes and six ties.
The Golden Bears maintained their lead through the opening minutes of the second half until a Crook 3-pointer sparked an 11-0 run to put USC ahead, 46-41, with 12:46 to play in regulation.
A pair of Brandon foul shots brought Cal within 62-60 with about a minute to play. Crook missed a jumper and then failed to connect on a pair of foul shots at the other end to keep it a two-point game.
Coming out of a timeout with 26 seconds left, Brandon grabbed the offensive rebound of a Clarendon miss and sank the game-tying jumper to force overtime.
The Golden Bears then dominated to extra period, outscoring USC by a 9-1 margin to snap a three-game losing streak against the Trojans.