Demetri Goodson scored 13 points and Jeremy Pargo had 12 for the Bulldogs (19-5, 10-0 West Coast Conference). Matt Bouldin had 11 points and Josh Heytvelt scored 10.
Dior Lowhorn led the Dons with 23 points -- hitting 4-of-4 from 3-point range -- and Blake Wallace connected on 5-of-6 3-pointers to finish with 19 points for San Francisco (9-17, 1-10). Kwame Vaughn scored 15.
Gonzaga took a 41-37 lead into the second half. Midway through the period, the Dons led 57-56, but Gonzaga got a five-point outburst by Pargo to key a 13-3 run that put the visitors up 70-59.
Wallace got San Francisco to within 77-73 with a 3-pointer during the game's closing seconds.