LAS VEGAS -- Arizona allowed Colorado to hang around for a half. Once the Wildcats got rolling, there was no stopping them on the way to the Pac-12 semifinals.
Lauri Markkanen scored 20 points, Allonzo Trier added 19 and No. 7 Arizona pulled away in the second half for a 92-78 victory over Colorado on Thursday night in the quarterfinals of the conference tourney.
"They were offensive juggernauts tonight," Colorado coach Tad Boyle said. "My hat goes off to them. They've got some good players. They're well-coached. They've got great balance inside and out."
Arizona (28-4) played a solid first half, building a one-point lead. Coming out of halftime, the Wildcats were nearly unstoppable, stretching the lead to 17.
The co-Pac-12 champions shot 56 percent, made 10 3-pointers and held nearly everyone except Derrick White in check on defense.
Dusan Ristic added 15 points for the Wildcats, who will play the winner between No. 3 UCLA and Southern California in Friday's semifinals.
"I think early on we struggled defensively," Trier said. "But I think we did some good things to make minor changes that helped pick it up in the second half. And I think it was good for us."
White finished with 31 points and Xavier Johnson had 20, but Colorado (19-14) had no answer when Arizona hit the gas in the second half. The Wildcats made 16 of 25 shots in the second half, including 6 of 8 from 3-point range.
"We lost this game on the defensive end," Boyle said. "There's no doubt about it."
Arizona shared the Pac-12 title with Oregon and was the No. 2 seed in the conference tournament after losing to the Ducks in Eugene.
The Wildcats won the only regular-season meeting with Colorado 82-73 in Tucson behind Kadeem Allen's stellar game at both ends.
The Buffaloes earned another shot at Arizona and a potential NCAA Tournament resume-boosting win after knocking off Washington State in the quarterfinals.
The first half of the rematch turned into a duel between White and Trier. White had 15 points, Trier scored 12 and the Wildcats had a 38-37 lead at the break.
Arizona turned the second half into a rout. The Wildcats opened with an 11-0 run to push their lead to 12 points.
Colorado tried to fight back with a 6-0 run, but Rawle Alkins and Markkanen hit consecutive 3-pointers to make it 60-47.
The Buffaloes cut it to nine after that, but got no closer, sending the Wildcats off the semifinals and possibly a high seed in the NCAA Tournament next week.
"No matter what happens this week, the one thing that I do know is it's about playing our best next week," Arizona coach Sean Miller said.
Arizona was superb at both ends of the floor after halftime, running away from a team playing for its NCAA Tournament future.
Colorado could have used a win over a top-10 team to boost its NCAA resume. Now the Buffaloes will have to wait to see where they'll play in the postseason.
Arizona point guard Parker Jackson-Cartwright had a quiet night scoring, finishing with four points on 1-of-2 shooting. He still had a major impact on the Wildcats' victory.
The 5-foot-11 junior grabbed seven rebounds, dished out seven assists and had no turnovers while orchestrating Arizona's offense. He has one turnover the past four games.
White had a rough game against Arizona the first time out, scoring seven points on 3-of-7 shooting. He was much better against the Wildcats in the quarterfinals, hitting 9 of 19 shots and all nine of his free throws to finish with the eighth-most points in Pac-12 Tournament history.
White also had six rebounds, five assists and two steals.
Colorado must wait to see if its resume is good enough for an at-large bid to the NCAA Tournament, but is most likely looking at playing in the NIT.
Arizona will play the winner between No. 3 UCLA and Southern California in Friday's semifinals.
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