"Utah ran the same play to Dean," said the UCLA coach. "So when Colorado had a 3 to tie the game, my heart was halfway down my stomach on that last shot by Booker."
But Booker missed, giving the Bruins their ninth straight victory, 78-75. Travis Wear scored 14 of his career-high 23 points in the second half and Jordan Adams' two free throws with 7 seconds left provided the three-point cushion.
Adams finished with 18 points for UCLA (14-3, 4-0 Pac-12). Shabazz Muhammad added 14 and Kyle Anderson 12 for the Bruins, whose winning streak is their longest since a 10-game streak in 2008-09.
"This is a great win over a very good team," Howland said. "I told our team today before the game that this is a sixth-ranked team in RPI and this is obviously a hard place to win."
UCLA, coming off a season-low 57-point scoring output, improved to 6-1 all-time against the Buffaloes.
Spencer Dinwiddie led Colorado (11-5, 1-3) with 23 points. Josh Scott and Booker had 18 each for the Buffaloes, losers of three of their last four.
"We played with too much inconsistency, and I am disappointed with that," said Colorado coach Tad Boyle. "Fourteen turnovers are too many to defeat a good team."
The Buffaloes gave up 17 points off turnovers. And they allowed UCLA to gain an additional 17 points with its fast break.
"The transition points," said Boyle, shaking his head. "We had made a goal of minimizing transition points."
After a sluggish first half, UCLA took a 42-37 lead on Wear's short jumper. Booker tied it at 42 with a 3-pointer.
Wear answered with another jumper that started a 14-2 run, capped by a 3-pointer and free throw by Adams, that pushed UCLA's lead to 58-45. Norman Powell kept it a 13-point edge with his own trey with 8:03 left, but Booker made two free throws to get Colorado back to 72-68.
"Our defense, first of all, was the difference in that stretch," Wear said. "We didn't allow them to make shots. I think we limited them to one shot each trip while we got easy transition buckets."
Dinwiddie's 3-pointer made it 74-71, and the Buffaloes began fouling immediately after each made basket, a strategy that paid off. Adams and Muhammad made only two free throws around another basket by Booker, and Dinwiddie made an uncontested layup to get Colorado to 76-75.
"I told (Dinwiddie) to take the shot that was there," Boyle said. "Make the shot and we'll take our chances with their free throws."
But Sabatino Chen chose to foul Adams, an 82 percent free-throw shooter. Adams sank both to make it 78-75.
"I'm just happy we're up and not on the losing end," Adams said. "So I'm just taking my time and making them."
Colorado had a final chance to tie, but Booker missed his 3-pointer at the buzzer.
"It didn't come down to the last shot," Dinwiddie said. "We had our chances."
Neither team was able to break free in the first half. There were four ties and 12 lead changes, and Colorado's largest lead was 23-19 after a 3-pointer by Xavier Johnson with 8:01 left.
The Bruins, meanwhile, managed first-half leads of no more than three points. The last one, 35-32, came on Wear's fadeaway in the final minute before halftime.