Leonard Washington had 14 points and 14 rebounds to help Wyoming beat a cold shooting No. 15 San Diego State 58-45 on Saturday night.
Larry Nance Jr. added 11 points and 12 rebounds, and Derrious Gilmore had 13 points for the Cowboys (15-2, 2-2 Mountain West).
Wyoming's win snapped a five-game losing streak to the Aztecs.
SDSU (14-4, 2-2) lost its second game in a row, the first time this season the Aztecs have lost back-to-back games. SDSU fell to UNLV on Wednesday.
Jamaal Franklin led SDSU with 13 points - 5 points below his season average.
The Aztecs, who entered the game averaging 72 points, struggled from the field Saturday night. They hit just 29 percent (17-of-59), making just 2-of-18 3-point attempts.