PULLMAN, Wash. (AP) Borislava Hristova had 13 of her 21 points in the second half and Washington State beat No. 25 Southern California 73-61 on Friday night.
Maria Kostourkova and Louise Brown added 10 points each for Washington State (12-5, 3-3 Pac-12).
Dawnyelle Awa assisted Hristova's weak-side cut to make it 68-61 with 1:41 left and the Cougars made 5 of 10 free throws while USC (14-3, 2-3) missed its last seven field-goal attempts.
The Cougars outscored USC 23-11 in the third quarter to take a 54-49 lead. The Trojans closed within one with the first four points of the fourth quarter, but Washington State answered with a 7-0 run to lead 61-53.
It was Washington State's first win against a ranked opponent since a 70-64 victory on Nov. 29, 2013, over No. 10 Maryland.
Kristen Simon had 19 points to lead USC. Sadie Edwards, Aliyah Mazyck and Temi Fagbenle added 10 each.