Stephen Holt scored 14 points, shooting 12-for-12 on free throws, and Jordan Giusti had a career-high 12 points for the Gaels (2-0) in a game that started at midnight local time and ended at 2:14 a.m.
Saint Mary's led 38-31 at halftime and used a 15-1 run midway through the second half to pull away.
Leading 47-44, Giusti started the spurt with a free throw, Matt Hodgson tipped in Giusti's miss on the second shot to put the Gaels up six. Giusti's layup capped a run of 11 straight points, and after a free throw by the Zips, Walker and Garrett Jackson had consecutive layups to increase the lead to 62-45 with just under 9 minutes remaining.
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.