Arizona struggled defensively and Butler took advantage as the Wildcats lost 69-65 Friday night in Las Vegas.
Lauri Markkanen and Kelan Martin scored to start the game. Avery Woodson made a three, but Kadeem Allen scored. Markkanen and Rawle Alkins then hit consecutive threes. Andrew Chrabascz made a three of his own as Butler led 11-10 at the media timeout.
Kamar Baldwin scored and Martin made a free-throw. Allen then had a three-point play and Markkanen scored again.
Parker Jackson-Cartwright made a free-throw, but Martin scored. Alkins and Martin exchanged baskets and Dusan Ristic got on the board.
Martin made a three, but Markkanen made one as well. Chrabascz and Alkins scored before Woodson got a four-point play to put Butler up 27-25 with just under eight minutes left.
Markkanen made one free-throw and Baldwin hit two. Markkanen made two more and a basket by Ristic gave the Wildcats a 30-29 lead with 3:47 left in the half.
Alkins scored and Ristic made two free-throws. Chrabascz then made four straight from the line. Sean McDermott scored to end the half with Butler up 34-32.
Martin and Allen scored to start the half and Ristic and Martin got a basket. Allen and Tyler Lewis exchanged buckets before a three by Woodson put Butler up 45-40 at the media timeout.
Kethan Savage got on the board and Baldwin followed with a basket to force Sean Miller to call timeout with the Wildcats down nine.
Allen made two free-throws and McDermott scored before a basket by Kobi Simmons cut the Butler lead to 51-44 with 11:38 left.
Lewis and Martin scored and Simmons made two free-throws. Markkanen made two from the line and Simmons scored again.
Baldwin got a bucket, but Jackson-Cartwright had a three-point play. A basket by Comanche and Simmons then put Arizona up 59-57 and forced Butler to call timeout with 5:22 left.
Simmons scored and McDermott made two free-throws before Chrabascz hit a layup to bring Butler within two.
Baldwin made two free-throws and Tyler Wideman had a three-point play to put the Bulldogs up three with 29 seconds left.
Chrabascz made a free-throw to seal the deal as the Wildcats lost their first game of the season.