MORAGA, Calif. -- Matthew Dellavedova was a thorn in BYU's side for the second time this season, scoring 20 points as Saint Mary's defeated the Cougars 64-57 Thursday night.

Dellavedova, who hit a halfcourt shot at the buzzer to give the Gaels a 70-69 victory over BYU on Jan. 16, was 6 for 14 from the field, including three 3-pointers, and hit 5 of 6 free throws.

Beau Levesque added 17 points for Saint Mary's (23-5, 12-2 West Coast), which has won 11 of its last 12 games. The Gaels, who are in second place in the WCC, now have a three-game lead over third-place BYU (20-9, 9-5) with just two conference games remaining.

Brandon Davies led the Cougars with 25 points and nine rebounds.

Saint Mary's shot 36 percent from the field but hit 22 of 26 free throws. BYU shot 51 percent but was just 12 of 19 at the foul line.