Colorado senior running back Rodney Stewart, playing in his last game on Folsom Field, made sure the Buffaloes wouldn't go winless in their first year of Pac-12 play.
Stewart rushed for 181 yards and three touchdowns on 24 carries as the Buffs rolled over Arizona 48-29.
Colorado outrushed the Wildcats 273 yards to 60.
Arizona quarterback Nick Foles threw for 352 yards but also tossed three interceptions.
The Buffs improved to 2-9 on the season and 1-6 in conference play, while the Wildcats fall to 2-8 and 1-7 as they battle to avoid the South Division basement.
Colorado is at UCLA next weekend. Arizona visits archrival Arizona State, the Wildcats' final conference game. They conclude their season on Nov. 26 against Louisiana-Lafayette.