The Wolfpack, which finished third in the Mountain West Conference last season, shot 41.1 percent, hitting 23 of 56 shots.
The Mustangs, meanwhile, were a frigid 31 percent from the floor, making just 18 of 58 shots, including 4 of 22 3-point attempts for 18.2 percent. Reese Morgan scored 13 points and David Nwaba 11 for Cal Poly, which reached the NCAA tournament last season as the Big West tournament champion.
Nwaba's free throw gave Cal Poly a 28-26 lead to start the second half. Nevada then went on an 8-0 run and never trailed after that. Leading by 11, the Wolfpack put together 9-2 run over the final 4:25.