BERKELEY, Calif. (AP) Despite a pretty rigorous non-conference schedule highlighted by two games against ranked teams, Arizona coach Sean Miller wasn't surprised his squad came out a little tentative in its Pac-12 opener.

A strong second half from freshman Kobi Simmons provided all the calming influence the 18th-ranked Wildcats needed.

Dusan Ristic scored 16 points and Arizona overcame a sluggish and sloppy first half to beat California 67-62 on Friday night.

Simmons added 14 points while Lauri Markkanen had 13 points and nine rebounds as the Wildcats (12-2, 1-0) rallied from 13 points down and used a big run coming out of halftime to extend their winning streak to six games.

''It was us just getting back comfortable and finding ourselves,'' Simmons said after Arizona won for only the second time this season after trailing at halftime. ''We know what we can do and we know the players we have. We just came out aggressive (in the second half) and got the job done.''

Arizona struggled from the perimeter most of the game before Simmons provided a big lift in the second half. The freshman guard scored 10 consecutive points as part of a 15-4 run coming out of halftime, made a key save at midcourt following an inbounds play under the Wildcats basket, then fed Rawle Alkins for a late dunk to help preserve the win.

''In the second half he gave our team confidence,'' Miller said. ''His spurt there got us the lead. I think we might have relinquished it but from that point on it was a different game.''

California (9-4, 0-1) made just nine field goals in the second half and shot 37 percent from the field overall. The Golden Bears have lost consecutive games at Haas Pavilion following a school-record 27-game winning streak.

Ivan Rabb had 16 points and a career-best 16 rebounds for California.

''I just think that, simply, guys that were defending the ball didn't take pride in defending,'' Bears coach Cuonzo Martin said. ''That's what happened in the second half. It's that simple.''

The game, featuring two of the Pac-12's best defensive teams, opened up following a slow first half when Miller burned a timeout less than 90 seconds in.

Arizona led 41-36 with 14 minutes remaining before Rabb sparked a mini-run that put California back in front. After the teams traded scores, Chance Comanche scored on a three-point play with 10:33 left that put Arizona ahead for good.

The Wildcats still had to hold off a late run by the Bears. Jabari Bird's 3-pointer pulled California within 66-62, and after a turnover near midcourt, Bird had a chance to pull the Bears closer but his 3-point attempt bounced off the front of the rim.

Bird finished with 16 points and seven rebounds.

The Bears used their conference-leading defense to set the tone in the first half when California's offense sputtered.

Nine days after limiting No. 12 Virginia to 22 points in the first half, the Bears limited the Wildcats to 26 and used a 15-0 run to take control.

Arizona had won five straight since losing to Gonzaga in the Naismith Hall of Fame game on Dec. 23.

BIG PICTURE

Arizona: It was a lot closer than it probably should have been but the young Wildcats kept it together and made the game-changing run when they needed to. The offense wasn't sharp early but Miller's group responded in front of a hostile crowd on the road.

California: For the second consecutive game the Bears played a Top 25 team tight but couldn't finish the job. Martin's team continues to shine defensively, although the problems on the offensive end are making it tough.

MILLER'S 200th

The win was the 200th at Arizona for Miller. Unlike many of his contemporaries, the Wildcats coach embraced the milestone moment. ''Any time as a coach you hit one of those it means something,'' said Miller, who is 200-63 at Arizona. ''Being a college basketball coach isn't easy, especially in this day and age when from one season to the next so many things can change.''

POLL IMPLICATIONS

As long as they can hold court against Stanford on Sunday there's no reason to think the Wildcats will lose any ground in the poll. There's a chance they could move up a few slots depending on what happens ahead of them, but for now Arizona's spot at 18 is secure.

UP NEXT

Arizona: Takes a short trip across the San Francisco Bay to play at Stanford on Sunday night.

California: Closes out its five-game homestand by hosting Arizona State on Sunday night at Haas Pavilion.

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