After trailing most of the game, the Sun Devils made three straight 3-pointers to go ahead for good. Rihards Kuksiks' long shot tied it at 44 with 6:04 left before Harden hit a 3 to give ASU just its second lead, 47-44. Kuksiks hit another shot from behind the arc for a 50-44 lead.
ASU outscored San Diego State 18-8 over the last 6:27, including five free throws down the stretch by Derek Glasser.
Kyle Spain scored 17 points for the Aztecs, who shot just 35.3 percent from the field.