Damyean Dotson added 16 points for the Ducks (19-5, 8-3 Pac-12), who had been on a slide after opening conference play with seven straight victories.
Oregon trailed 30-22 after the first half but pulled in front midway through the second and extended its lead to 53-45 on Carlos Emory's tip-in with 6:32 left. The Ducks led by as many as 13 points down the stretch.
Jason Washburn had 20 points and seven rebounds for the Utes (10-13, 2-9), who lost their second straight after a victory over Colorado, which upset Oregon 48-47 on Thursday night. The Buffaloes scored the final eight points to snap Oregon's 20-game winning streak at home.
The Ducks were without freshman point guard Dominic Artis for the fifth straight game because of a left foot injury. He averages 10.2 points and a team-leading 3.8 assists for the Ducks, and his steadying influence has been missed.
Both teams got off to rather slow starts. Oregon went up 13-10 on Arsalan Kazemi's dunk with 8:59 left in the first half. Utah went ahead 19-18 on Jordan Loveridge's jumper.
Oregon's recent struggle with turnovers continued, and the Ducks committed 10 within the first 16 minutes. Oregon went into the game with an average of 16 turnovers per game, most in the Pac-12. They finished with 17 against the Utes.
The Utes extended their lead to 27-20 on Brandon Taylor's jumper with 1:46 left, and Washburn's 3-pointer at the buzzer put Utah ahead 30-22 at the break.
Oregon pulled to 32-31 on Singler's 3-pointer early in the half, but Utah wouldn't let the Ducks take control yet. Brandon Taylor hit a 3-pointer to put the Utes up 37-31.
Johnathan Loyd, a 5-foot-8 junior starting in place of Artis, made a 3-pointer that narrowed it to 43-41 with 11:26 left but then took an elbow to the face from the 6-foot-10 Washburn. Loyd went to the bench for treatment, but later returned.
The momentum shifted to Oregon and Singler's layup tied it at 43 before Oregon went ahead on Kazemi's free throw.
Kazemi finished with 11 points and 14 rebounds for his first career double-double.
The Ducks climbed to No. 10 in the AP poll after winning all but two of their non-conference games and opening Pac-12 play with seven straight wins. It was Oregon's best league start in 87 years, and their highest ranking since late 2007.
But last week, Oregon lost to Stanford and California. The return home to Matthew Knight Arena was supposed to bring the Ducks some relief, but the Buffaloes hung tough for their first victory in Eugene since 1955.
The losing streak dropped the Ducks out of first place in the Pac-12. Oregon is in a tangle for second behind No. 7 Arizona.