LOS ANGELES -- It was late, the crowd was sparse and the game was ugly.
Andre Roberson still had Utah's number.
The sophomore forward had 20 points and 11 rebounds -- his third double-double of the season against the Utes -- to help Colorado pull away in the second half of a 53-41 win in the opening round of the Pac-12 tournament on Wednesday night.
"We never got in a rhythm offensively all night," said Buffaloes coach Tad Boyle, who picked up his 100th career victory. "It was kind of an ugly win, but we'll take it and move on."
Carlon Brown added 15 points and Spencer Dinwiddie 10 for the sixth-seeded Buffaloes (20-11), who notched consecutive 20-win seasons for the first time in the program's 111-year history, having won a school-record 24 games last year in the Big 12.
"I told these guys we have an opportunity to leave a legacy, and this team has done that. Both of these guys are part of two teams that did that," Boyle said about Roberson and Brown.
"As we got around that 17, 18 mark, we laid it out there as a challenge. That's something these guys can take with them."
Colorado advanced to a quarterfinal game Thursday against No. 3 seed Oregon at Staples Center. The Ducks (22-8) had a first-round bye. The teams split in the regular season.
Jason Washburn led the 11th-seeded Utes (6-25) with 11 points, their only player in double figures. They finished 0-13 away from home in their first season in the Pac-12, including 0-4 at neutral sites under first-year coach Larry Krystkowiak. He presided over the school's first season of 20 or more losses.
"Good teams win on the road," Krystkowiak said. "We have to fix what's broken, and there are so many elements we have to work on. We need to improve, and that starts when we get back to Utah. We need to get in the gym and in the weight room, and have the dedication and prove that we deserve to play in the Pac-12."
The Buffs began the game by missing 10 of their first 11 shots during a 10-minute scoreless stretch. They recovered to start the second half, scoring 10 in a row to go up 35-25. Dinwiddie had four points in a row, and Roberson added four.
"We missed some easy shots under the rim," Brown said. "We just didn't have a flow. We built this program on defensive rebounding and really stuck to it tonight. Without that we wouldn't have won. Some days, it's going to be ugly. Some days, we're going to be hot, but today just wasn't one of those days."
After Krystkowiak was called for a technical, the Utes scored the next eight straight to close to 35-33. Even during Utah's run, both teams went more than four minutes without scoring, one of a few droughts during the game.
The Utes played the second half with Anthony Odunsi, Kareem Storey and Chris Hines in foul trouble, and Storey and Odunsi ended up fouling out.
"We're young and inexperienced, but we fought hard and competed," Hines said. "We got a little winded in the second half and we didn't get a lot of calls."
But they again got within two points on a pair of free throws by Washburn with 6:12 remaining.
"It seems like it's always one or two plays or mistakes that keeps us from winning on the road," Washburn said.
From there, Colorado outscored the Utes 16-4 to end the game. Roberson's rebounds gave him 347 for the season, breaking the 58-year-old school record.
"It means a lot, but I'm not into all the individual praise," he said.
The Buffs dominated the paint, 22-12, and scored 19 points off Utah's 18 turnovers.
Colorado scored the game's first four points, then went scoreless for the next 10 minutes as Utah took an 11-4 lead.
The Buffs got back into the game as Roberson and Brown combined to score 12 consecutive points for a 20-16 lead. The teams traded baskets the rest of the half, with Dijon Farr hitting a 3-pointer at the buzzer that left the Utes trailing 25-23 at the break.
It was the lowest-scoring of the teams' three meetings, all won by the Buffs, who beat Utah by 40 points in their first game.