Holt was 5 of 9 from 3-point range for the Gaels (14-4, 3-1 West Coast). Dellavedova scored 18 points. James Walker III had 13 points and seven rebounds, and Mitchell Young had 10 points and seven rebounds. Brad Waldow had seven rebounds.
BYU (14-5, 4-1) led 34-27 at halftime. In the second half, the Gaels were 7 of 11 from 3-point range.
Dellavedova made a free throw, tying the game at 65 with 1:48 to play. Tyler Haws put BYU up with a jumper, but Dellavedova scored, tying the game again. Haws hit a jumper with 2 seconds to play. Dellavedova hit a 3-pointer at the buzzer to give Saint Mary's the win.
Mike Brey is looking at former Notre Dame players to fill two assistant jobs that have opened up with the departures of Martin Ingelsby and Anthony Solomon.
Purdue's 2016-17 prospects got a jolt Wednesday when forward Caleb Swanigan announced he will return for his sophomore season.
Clemson's Jaron Blossomgame says he is withdrawing from the NBA draft and returning to school for a final season.