Washington State's Klay Thompson scored 20 points, including a key jumper late, to give the Cougars a 67-60 win against USC on Thursday night at the Galen Center.
Thompson, the Pacific 10 Conference's leading scorer with an average of 22.9 point entering the game, hit a jumper with 1:05 left to put Washington State ahead, 64-58, essentially sealing the win.
With USC leading, 42-28, the Cougars used a 26-11 run to go up 54-53.
USC (11-7 overall, 3-3 in Pac-10 play) had a five-game home winning streak snapped. USC had a chance to move into a three-way tie with California and Arizona State for first place in the league standings. The Golden Bears won Thursday over Oregon while the Sun Devils were idle.
Washington State (14-5, 4-3) won its second straight and faces UCLA Saturday.
Marcus Johnson led USC with 16 points.
-- Baxter Holmes
Photo: Washington State's Xavier Thames strips the ball from USC forward Alex Stepheson, who was trying to score over the Cougars' Charlie Enquist in the first half Thursday night. Credit: Alex Gallardo / Associated Press