CAL FALLS SHORT AGAINST ARIZONA By JOHN AKERS Mercury News Staff Writer BERKELEY -- Damon Stoudamire played what might have been the best 20 minutes of his life Thursday, enough to propel No. 13 Arizona to a 99-86 victory over No. 20 Cal. Stoudamire scored 21 of his 26 points in the first half, outdueling Cal's Monty Buckley, who scored 19 of his 27 in the opening 20 minutes, which ended with the Wildcats leading 46-34. Stoudamire, guarded by Anwar McQueen, was held scoreless for the first 14 minutes of the second half, but the Wildcats (11-3 overall, 1-1 in the Pacific 10 Conference) managed to hold off the Bears (8-3, 1-2). The Bears pulled to within 49-45 soon after Michael Stewart blocked three of four Arizona shots and got the sellout crowd back into the game. But the Wildcats soon worked their lead back to 60-50. They never trailed by fewer than 10 points over the final 10 minutes. Stoudamire opened the first half with a long three-pointer and ended it with a 20-footer. In between, he beat the Bears defenders with three-point shots taken from well beyond NBA range, by beating his defenders off the dribble and by beating the Cal defense downcourt on the fastbreak. Stoudamire scored his 21 first-half points on 9-for-11 shooting, plus he had five assists and four rebounds. Buckley was a worthy adversary, however. He scored 10 points in one 71-second stretch that took the Bears from a 21-12 deficit to a 22-21 lead. Soon after, Stoudamire took over again. He drove K.J. Roberts hard into the lane, stopped and hit a jumper. Then he hit a three-pointer. Corey Williams added a three-pointer, and Ben Davis a tip-in, and the Wildcats held a 37-26 lead. The Bears went six possessions in a row without scoring. That stretch ended with Coach Todd Bozeman calling a timeout and venting his anger at them. The Bears made 13 of 35 shots in the first half, for 37.1 percent. The Wildcats made 20 of 32, for 62.5 percent. The Wildcats played much of the first half without freshman guard Miles Simon, who landed on his wrist at the end of a fastbreak layup.