Once the Wildcats got rolling, there was no stopping them.
Stanley Johnson had 19 points, Brandon Ashley added 15 and No. 5 Arizona ran away from Cal in the second half for a 73-51 victory Thursday in the Pac-12 tournament quarterfinals.
"The familiarity, the intensity [of conference tournaments] can sometimes catch you off-guard," Arizona Coach Sean Miller said. "I don't know if it necessarily caught us off-guard, in the first half, but we really regained who we are in the second half."
Top-seeded Arizona (29-3) had trouble shaking the Bears in a rough first half before taking control with a run sparked by its defense early in the second.
Rondae Hollis-Jefferson had 10 points, six rebounds and was the catalyst for Arizona's defense.
T.J. McConnell added 13 points and six rebounds for the Wildcats, who will play UCLA on Friday in a semifinal.
"They played well in the first half and we kind of stagnated," McConnell said. "Credit Cal for that, but we made the plays when we needed to."
No. 8 seed Cal (18-15) played better than it did in two blowout losses to Arizona during the regular season, but faded after the Wildcats made their second-half run.
Tyrone Wallace had 19 points to lead the Bears, who shot 34%. David Kravish had 12 rebounds, but was held to six points on three-for-13 shooting.
"It's tough when you don't establish a post presence," Cal Coach Cuonzo Martin said. "We need spacing around the floor and move the ball out of the post to find shooters."
Oregon, seeded second, broke out from a tight game with its pressure defense, creating a string of turnovers to build an 18-point second-half lead.
Colorado, seeded 10th, made a late charge, but the Ducks earned a spot in a semifinal.
Jalil Abdul-Bassit added 15 points for Oregon, which scored 27 points off Colorado's 13 turnovers.
Young, the Pac-12 player of the year, also had seven rebounds and four assists.
Josh Scott had 16 points and Dominique Collier added 14 for the Buffaloes. Askia Booker had 12 points, five rebounds and five assists.
Utah 80, Stanford 56: The Utes (24-7), who trailed by five points at halftime, blitzed the Cardinal with a 46-17 edge in the second half. Delon Wright scored 20 points and Jordan Loveridge 18 for Utah. Chasson Randle led Stanford (19-13) with 22 points.