Foster missed all six of his shots inside the arc but was 5 of 11 on 3-pointers. Marc Trasolini added 14 points and 10 rebounds, and Yannick Atanga grabbed 13 boards for the Broncos (12-3), who had arguably the worst season in WCC history in 2011-12, going 0-16 in conference play.
Cole Dickerson had 17 points and 12 rebounds for the Dons (7-7), and Cody Doolin scored 16 points and dished out eight assists.
Santa Clara led 39-28 at halftime and by as many as 19 in the second half, but San Francisco pulled within 69-67 on Doolin's layup with 31 seconds left. Five free throws by Evan Roquemore, Foster and Trasolini helped seal the Broncos' victory.