LAS VEGAS – Nick Johnson had 18 points and drove inside to score with 34 seconds left to help the Arizona Wildcats hold off Colorado and win 79-69 in the Pac-12 Tournament quarterfinal.

The win moved Arizona (25-6) into a Pac-12 Tournament semifinal game against UCLA on Friday at 6:06 p.m.

The Wildcats lost twice to the Bruins during the regular season. They were beaten 84-73 at McKale Center on Jan. 24 and 74-69 in Los Angeles on March 2.

Colorado dropped to 21-11 but is still expected to get a NCAA tournament at large berth.

Arizona led 54-40 with 14:34 left when Jordin Mayes hit his second three-pointer of the game but Colorado gradually cut it back and trailed just 71-69 after Mark Lyons committed a turnover and Andre Roberson made two free throws just before the final minute.

 But then Johnson drove inside for a score that made it 73-69 with 34 seconds left and the Wildcats went 6 of 6 from the free throw line as Colorado fouled in the final 24 seconds.

While Johnson led UA with 18 points, Solomon Hill had 13 points and seven rebounds, and Mark Lyons added 14 points. Lyons made just 2 of 9 three-pointers but his a difficult twisting three down the stretch.

The Buffs struggled inside center Josh Scott battling foul trouble and Shane Harris-Tunks hurt, and UA took a 39-28 halftime lead. Arizona scored 15 points off 10 Colorado turnovers in the first half.

The Wildcats and Buffaloes both shot about 45 percent from the field, but five UA players had a steal, The Wildcats’ last score was typical. Colorado’s Sabatino Chen turned the ball over and Solomon Hill converted it into a three-point play, giving UA the 39-28 advantage.

Arizona also had a balanced offense in the first half, with six players scoring five or more points, with Nick Johnson leading the Wildcats with eight points. UA also had 18 total points from its bench players, including six from Brandon Ashley and two from Angelo Chol. 

With Scott having committed two early fouls and Harris-Tunks having his head, Colorado initially turned to Ben Mills, who only played in six games this season.

The Buffs also tried putting forward Andre Roberson at center, prompting UA to match up with Chol.

Colorado pulled to within 13-11 with 13:43 left in the half but Arizona rattled off seven straight points, including a three-pointer by Jordin Mayes, to take a 20-11 lead.

Mills had not taken a free throw when he went to the line with 7:45 left. Mills hit 1 of 2 free throws and Arizona led 23-18 at that point before the Wildcats took double-digit leads later in the first half.

Arizona took an early 11-8 lead at the first media timeout, making 5 of 7 shots to start the game while Colorado committed three turnovers.