Brevin Knight added 21 points for Stanford (11-1 overall, 2-1 in the Pacific 10), which led throughout the second half and never let the Sun Devils get closer than three points in the final 20 minutes.
The Cardinal made 31 of 33 free throws, including 13 of 13 in the first half.
Mario Bennett and Ron Riley scored 17 points apiece for Arizona State (11-3, 1-1), which trailed, 35-29, at halftime and watched Stanford use a 9-2 run to open a 44-31 lead with 16:13 to play.
Stanford stretched the lead to as many as 17 points late in the second half, making six consecutive free throws over a 23-second span ending with Harbour's two shots to make it 89-72 with 1:15 to go.
Stanford shot 63% and held the Sun Devils to 44%.
The two teams played fairly evenly in the first half, but Stanford was able to stretch the lead to as many as eight points twice. Todd Manley's basket with 2:36 left gave the Cardinal a 31-23 lead. Knight's shot then made it 33-25.
Andy Poppink had 12 points for Stanford.
Isaac Burton and Jeremy Veal both contributed 14 points for the Sun Devils.
Arizona (11-3, 1-1) went on a 9-0 run, including all five of Stoudamire's second-half points, with eight minutes left to turn a 65-60 lead into a 14-point margin. The Wildcats were not threatened again.
Monty Buckley had a career-high 27 points for Cal (8-3, 1-2), which lost its conference home opener.
Arizona avoided losing its opening two conference games for the first time since Lute Olson took over as coach in 1983-84. The Wildcats lost their league opener at Arizona State last week.
More UCLA Basketball
* If you follow UCLA basketball and want to review the Bruins' season to date, you can read features, game stories and notes that have appeared in The Times this season on TimesLink.
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