"These guys never quit. They never gave up," UCLA coach Ben Howland said. "They never stopped believing in themselves and each other and really found a way to battle back. "
Wearing uniforms with sleeves and matching camouflage-patterned shorts, the Bruins (24-8) got off to a groggy start and appeared to be in danger of becoming the second straight top seed to lose its first game in the Pac-12 Tournament.
Muhammad gave UCLA the spark it needed with a highlight-reel dunk over Arizona State center Jordan Bachynski and scored 10 points during a 17-4 second-half run that got the Bruins back in it.
No. 18 Arizona 79, Colorado 69 • At Las Vegas, Nick Johnson scored 18 points and hit a contested shot with 34 seconds left, helping Arizona beat Colorado in the quarterfinals.
Arizona (25-6) led by 14 in the second half, but had trouble shaking the desperate Buffaloes (21-11).
Johnson hit his shot between three defenders to put the Wildcats up four and followed teammate Mark Lyons' two free throws by swatting Askia Booker's 3-point attempt into Colorado's bench.
Lyons had 14 points and Solomon Hill 13 for Arizona, which moves on to face UCLA in Friday's semifinals.
Colorado won last year's conference tournament with four wins in four days and opened this year's tournament with a six-point victory over Oregon State. Now the Buffaloes will have to wait for the selection committee to make its decision.
• UCLA 80, Arizona State 75
• Arizona 79, Colorado 69
• Utah 79, California 69 (OT)
• Oregon 80, Washington 77 (OT)
• UCLA vs. Arizona, 7 p.m., Pac-12 Network
• Utah vs. Oregon, 9:30 p.m., ESPN