Isaiah Thomas had 21 points and 11 assists, and Washington overcame an eight-point halftime deficit and 43 points from Washington State's Klay Thompson to defeat the Cougars 89-87 Thursday in the Pac-10 tournament quarterfinals in Los Angeles.

Thompson's career high came on 15-of-29 shooting, including 8 of 14 from 3-point range, but it wasn’t enough as Thomas and C.J. Wilcox combined to score the last 16 points for Washington.

The Huskies (21-10), who snapped a two-game losing streak to the Cougars, will meet Oregon in the semifinals Friday.

Washington State (19-12) started quickly behind 18 first-half points from Thompson and led by as many as 13 points. But Washington erased an eight-point halftime deficit, and took its first lead of the game with 17:45 left on a tip-in by Matthew Bryan-Amaning.

The teams exchanged the lead several times in the second half and Washington led 84-82 with 48 seconds left when Thompson stepped to the line and missed the first of two free throws. He made the second, but Thomas scored four points in the final minute.

Terrence Ross scored 17 points for Washington, while Wilcox and Bryan-Amaning had 16 apiece. Justin Holiday had 12 points and 10 rebounds.