Thomas knocked down three 3s in the second quarter, and the Wildcats led by as many as 20 points, despite just a pair of free throws and a layup from McDonald in the period.
UCLA struggled with Arizona’s aggressive defense, committing nine first-half turnovers and 15 for the game. Kayla Owens hit a 3-pointer with 9 seconds left, helping UCLA cut its halftime deficit to 47-32.
The Bruins made it a 13-point game early in the third, but McDonald drove for another layup and was fouled. Her free throw gave Arizona 56-37 lead at the 7:53 mark.
“Some stuff got revealed,” Close said. “The question is, will we use this adversity correctly to buy a ticket to maybe a place that we couldn’t go otherwise.”
UCLA went more than nine minutes without making a basket in the the third, and the Wildcats led by as many as 31 in the fourth quarter.
McDonald received a standing ovation when she checked out of the game for good with 5:12 left to play.
“We came out with the eye of the tiger,” Arizona coach Adia Barnes said. “Huge win for us against a very good team. We continue to do things that no one expected, but we expected. … We know nationally it’s an upset but we feel like we can play with anyone. That’s just kind of our standard.”
UCLA: The Bruins have reached the most difficult part of their Pac-12 schedule. Four of their next five opponents are ranked in Top 25, starting with Arizona State on Sunday. Then they’re at No. 6 Stanford, and on Feb. 14 host No. 3 Oregon. Three days after that, they host No. 10 Oregon State.
Arizona: The Wildcats moved to 3-3 against Top 25 teams this season, and Barnes said having every player healthy after some injuries early in the season made a difference Thursday. Oregon and Oregon State on the road remain on the schedule, along with a home game against Stanford.
After McDonald hit her back-to-back 3s in the first quarter, she tried another and air-balled it. She laughed and shrugged her shoulders on her way back up the court to the delight of the crowd and her teammates on the bench.
“I had a little heat check I air-balled. But I was good,” McDonald said with a smile. “I felt different today.”
A nine-second moment of silence in honor of the nine victims of last Sunday’s helicopter crash in California that claimed the life of Lakers legend Kobe Bryant and his daughter Gianna, was observed inside the McKale Center before tipoff.
UCLA faces No. 19 Arizona State — a winner in triple overtime over USC earlier Friday — on Sunday afternoon.
Arizona: Hosts USC on Sunday afternoon.
More AP women’s college basketball: https://apnews.com/Womenscollegebasketball and https://twitter.com/AP_Top25