Iolani alum Derrick Low led Washington State with 15 points.

The third-seeded Trojans will face fourth-seeded Oregon in Saturday's championship game at Staples Center. The 16th-ranked Ducks beat eighth-seeded California 81-63 earlier Friday night.

USC (23-10) and Oregon (25-7) both reached the finals for the first time since 2003, when the Ducks beat the Trojans 74-66 in the title game.

Taj Gibson had 15 points and nine rebounds, Lodrick Stewart also scored 15, and Nick Young added 10 for the Trojans, who shot 10 of 16 from 3-point range and 18 of 38 overall (47.4 percent).

The Cougars made 11 3-pointers, but attempted 30 and shot 36.1 percent overall. USC went 24 of 33 from the foul line, while Washington State was 6-of-8.

Derrick Low, an Iolani alum, led second-seeded Washington State (25-7) with 15 points. Kyle Weaver scored 13 and Taylor Rochestie added 11 before fouling out with 8 seconds left.

The Cougars swept the Trojans during the regular season, but were extended in both games, winning 58-55 on the road and 88-86 in double overtime at home in the regular-season finale last weekend.

Pruitt scored eight straight USC points during a 13-5 run, putting the Trojans on top 56-46. Washington State scored six in a row to draw within four before two free throws by Stewart and a basket by Gibson made it 60-52 with 3:53 left.

The Cougars weren't closer than five points after that.

USC went ahead for good in the opening 7 minutes. Stewart, who had only six points in USC's 83-79 overtime victory over Stanford in the quarterfinals, scored eight straight to give the Trojans a 23-14 lead.

Pruitt made two 3-pointers and Young added another, making it 32-22 with 7:13 left before halftime. USC was 8-of-11 from 3-point range and 2-of-6 from inside the arc at that stage, and Pruitt had four 3-pointers and 15 points.