Only this time, they didn't have the crowd on their side like they did last time when it overcame a 17-point deficit to beat the Buffaloes 71-58 in overtime.
The Buffs avenged their heartbreaking loss last month when Sabatino Chen's apparent game-winning 3-pointer at Arizona was waved off at the end of regulation even though replays showed the shot was taken in time.
"When you can't match a team in this atmosphere, they're going to be playing downhill all the time and we're going to be playing up hill," Wildcats forward Solomon Hill said. "This is not a team to be playing uphill against.
"They're a very fast team.
Spencer Dinwiddie scored 19 of his 21 points in the second half and freshman Xavier Johnson added 19 points and nine rebounds as the Buffaloes dominated from start to finish and toppled a ranked team for the second time in a week.
"It's not that tough a loss," Hill insisted. "It's hard to play in some places in the Pac 12. I give Colorado a lot of credit, they came out and they were an aggressive team from start to finish.
"Xavier Johnson hit a buzzer-beater ... both of them hit a couple of buzzer-beaters that you just can't do anything about. So when guys like that are feeling it, there is not too much you can do to slow them down."
The Buffaloes (17-7, 7-5 Pac-12) have won six of seven, and this win over the Wildcats was by far their most impressive yet. They played stingy defense, moved the ball efficiently, held their own on the boards and controlled the tempo from tip-off to buzzer.
"What makes this win sweet is it has nothing to do with revenge," Colorado coach Tad Boyle said. "It has everything to do with the respect I have for Arizona and Sean Miller and their basketball program. We beat a top 10 team in the country that's legitimate and they're going to win a lot of games as this season unfolds.
"And I think if we play the way we did tonight we will, too."
The Wildcats (20-4, 8-4) had no answer for Dinwiddie or Johnson and were cold from the field, shooting 42 percent overall and 5 for 19 from beyond the arc. Hill led Arizona with 12 points and Mark Lyons had 11.
"It's never as bad as it seems and the sky isn't falling," Miller said.
The Buffaloes led 30-23 at halftime and were never seriously threatened over the final 20 minutes.
"I thought Colorado had an incredible environment. This was a big game for them," Miller said. "They're playing really well. ... This is a pivotal home game for them. They were ready to go."
Colorado started the second half with three free throws from Dinwiddie that gave the Buffaloes a double-digit lead. Dinwiddie added a dunk off a steal by Johnson and Andre Roberson's 3-pointer made it 38-23 with 17:50 left, prompting Miller to call his second timeout.
The Wildcats got back in it with consecutive 3s from Lyons and Nick Johnson, and when Grant Jerrett hit a 3-pointer from the top of the circle, the Wildcats had chipped the lead down to 45-39 with 10:43 remaining.
After Boyle's timeout, the Buffs went on an 8-0 run. Dinwiddie had a fast-break basket and a 3-pointer during the spurt that reserve Xavier Talton started with a 3 that got the crowd going again.
The Buffaloes didn't blow their big lead this time, unlike last month, when they squandered a 10-point lead over the final 2 minutes of regulation in Tucson before losing 92-83 in overtime.
The Buffaloes didn't let go of that loss very easily, or very quickly. Several weeks later, Colorado's game notes showed they were still smarting over the call when the school said the Buffs had 11 3-pointers against the Wildcats—only 10 of which counted.
Chen got one of the loudest ovations from the sellout crowd at the Coors Events Center—an audience that included John Elway at courtside—when he entered early in the first half.
Miller said "it would have been hard" for any opponent to have won in Boulder on this night.
"I think some of the best teams in the country would have had to come in here and play a great game," he said. "This was an electric atmosphere and playing against a team that played really hard and they were ready and they played really well on offense. I thought Xavier Johnson was great; he probably doesn't get enough national recognition. I'm not so sure he's not the best freshman in our conference. If he's not, he should be certainly put up there with the three or four others that everybody acknowledges."
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