Galdeira scored 14 of her points in the second half when the Cougars (15-11, 6-9 Pac-12) shot 55.6 percent. Tia Presley had 17 points, Mariah Cooks 16, 12 in the second half, and Dawyelle Awe had all 11 in the second half when the lead ballooned to 22.
The margin of victory was the biggest since a 51-38 win on Feb. 27, 1976. The teams play again on Sunday afternoon.
The Cougars were up by eight midway through the second half when Awa hit a 3 to start a 14-0 run, capped by Pressley’s three-point play at 6:18 for a 76-54 lead.
Washington State, which had lost 36 straight to its rival before sweeping them last year for the first time in 39 years, had not beaten Washington by double figures since a 70-60 win on Jan. 10, 1981, which was the last game of the last three-game winning streak for the Cougars.
Jazmine Davis had 23 points for the Huskies (19-8, 8-7). Kelsey Plum, who had her conference record string of free throws end at 35, had 18 and Federal Way’s Talia Walton 14.
Washington State used an early 12-0, with Presley and Galdeira score five points each, to take a 17-4 lead. But the Huskies scored the last 14 points of the half, seven by Davis, who had 17 in the half, and four by Walton, to lead 38-33 at the break.