Olynyk connected on 13 of his 17 shots while Elias Harris provided 17 points with 13 rebounds for the Bulldogs (25-2, 12-0 WCC), who posted their first road win against San Francisco since the 2008-09 season.
The victory enabled Gonzaga to remain undefeated in West Coast Conference play.
The Dons (11-15, 4-9) got 15 points from Cole Dickerson and 14 from Cody Doolin.
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