San Diego (9-14, 4-7 West Coast) twice had 19-points leads early in the second half before Santa Clara (8-15, 0-10) cut the margin to 68-65 when Evan Roquemore hit two free throws with 12.6 seconds left. But Dennis Kramer made a pair of free throws with 11.6 seconds left for the final margin.
Dee, a freshman, hit five 3-pointers for the Toreros, who held a big advantage at the free-throw line. San Diego made 25 of 39 free throws, while the Broncos were 15 of 18 in a game where 47 total fouls were called.
Christopher Anderson scored 13 points for San Diego.
Roquemore scored all of his 21 points in the second half while Denzel Johnson added 20 points.