Arizona Wildcats forward Brandon Ashley (21) passes through UCLA Bruins forward Travis Wear (24) and UCLA Bruins guard Larry Drew II (10) in the first half of the semifinals in the PAC-12 Tournament at the MGM Grand Garden Arena. Friday March 15, 2013 Las Vegas, Nevada

Mamta Popat / Arizona Daily Star

LAS VEGAS – The Arizona Wildcats tore the heart out of UCLA’s offense tonight, but it turned out the Bruins had another trick up their sleeves.

His name was Jordan Adams, the freshman wing who scored 18 of his 24 points in the second half while leading UCLA to a comeback 64-62 win over UA in the Pac-12 Tournament semifinals tonight at the MGM Grand Garden.

The Wildcats opted to invest top defender Nick Johnson on Larry Drew II -- which largely  worked while Drew went scoreless with four assists -- and UA also kept UCLA standout Shabazz Muhammad to just two points in the secondhalf.

But Adams caught fire in the second half. He hit a number of tough shots around the basket, while making 11 of 13 free throws, and scored 13 straight points for UCLA at one point. Meanwhile, Muhammad scored nine points in the second half as UCLA overcame an 11-point UA lead.

While Adams missed his final attempt, with the game tied at 64, Kyle Anderson rebounded and put it back for the game-winner. UA had a final possession but went to Solomon Hill at the end. Hill stepped inside the three-point line and missed an 18-footer.

The loss dropped UA to 25-7 while UCLA improved to 25-8. The Wildcats will learn their NCAA tournament fate on Sunday at 3 p.m., with their chances of receiving a preferential 1-4 seed possibly having been reduced.

UA has not beaten a Top 35 RPI team since Christmas, when it beat San Diego State in the final of the Diamond Head Classic.

UCLA tied it at 56 after UA coach Sean Miller was whistled for a technical foul and Jordan Adams hit the two ensuing free throws. While Hill followed that by throwing down an emphatic dunk, Adams tied it up again at 58 – the 13th straight points he scored for UCLA to that point.

Finally, Muhammad hit 2 of 2 free throws to give UCLA its first lead,60-58, with 3:11 left. UCLA later went ahead 62-60 o a three-point play by Travis Wear and, after Kaleb Tarczewski made 1 of 2 free throws, Adams again made a big play.

Adams stole the ball from UA’s Mark Lyons, drove downcourt and drew a foul from Tarczewski – which resulted in Tarczewski fouling out and Adams hitting two more free throws to give UCLA a 64-61 lead.

Grant Jerrett then hit a three-pointer to tie it at 64 before Anderson hit the game-winner.

Leading by four points at halftime, Arizona kept up its defense early in the second half. The Wildcats took a 49-38 lead with 10:24 left before UCLA made a comeback.

The Bruins rattled off nine straight points while Muhammad scored twice inside and drew fouls both times. He had five points on the two plays and Adams had another score to cut UA’s lead to 49-47 with 8:14 left.

In the first half, Arizona kept Muhammad to just only two points on 1-of-4 shooting and  Drew went scoreless with only one assist while being defended primarily by Johnson. The Wildcats led 30-26 at halftime.

Overall, the Bruins shot just 34.4 percent from the field in the first half. While UA had eight turnovers, the Wildcats outrebounded UCLA 21-16.

Offensively, Arizona was led by forward Brandon Ashley, who had nine points on 4-of-5 shooting while displaying plenty of aggressiveness. The Wildcats also received seven points from Johnson and six from Hill.

Arizona took its biggest lead of the first half, 26-18, after Hill made a pair of three pointers with about five minutes left.

But Adams hit four free throws for AUCLA over the next minute to pull the Bruins within four and the game stayed within two baskets the rest of the half.

UCLA will now face the winner of the Oregon-Utah semifinal in the Pac-12 Tournament final Saturday at 8:02 p.m. on ESPN.