AUSTIN, Texas (AP) - For Colorado, the NCAA tournament was all about momentum.
The Buffaloes were making consecutive appearances for the first time in 50 years. As a No. 10 seed in the East, they were a trendy pick for a mild upset over No. 7 seed Illinois.
They even fought back from a 16-point deficit with a 21-0 run in the second half to take the lead.
But all that momentum disappeared in one 30-second span late in the game when Illinois made consecutive 3-pointers to regain the lead and pull away for a 57-49 victory Friday.
The Illini (23-12) advanced to play Sunday against No. 2 seed Miami. Colorado (21-12) has to go back home.
"Our defense was good enough in the second half, our heart was good enough,'' Colorado coach Tad Boyle said. "We're disappointed being one and done. ... It's reality. We have to live with that another year.''
The 3-pointers from guards Brandon Paul and D.J. Richardson rescued the Illini from an epic meltdown. Illinois, a team that came in with confidence built by playing through the rigors of the Big Ten schedule, was in control in the first half.
Illinois used its defensive muscle and a 21-5 run over the final 10 minutes of the first half to roll into the locker room with a 37-21 lead. Richardson made three 3-pointers during the run and Tracy Abrams capped it with Illinois' sixth 3-pointer of the half with 3 seconds left.
Everything flipped in the second.
Colorado regrouped behind Pac-12 defensive player of the year Andre Roberson and the hot shooting of Aski Booker, who made three 3-pointers in the opening minutes of the second half. Booker finished with 14 points.
Paul picked up two quick fouls early in the half and went to the bench. His absence over the next 3 minutes seemed to unsettle the Illini as Colorado kept chipping away at the lead. Even when Paul returned, he missed his first two shots and the Illini scored just two points over the first 9 minutes of the half.
Colorado made the hard work pay off when Josh Scott's layup gave the Buffaloes the lead, and baskets by Xavier Johnson and Roberson pushed it to 44-39. Illinois finally broke its scoring drought on a basket by Abrams with 8:30 left.
The game finally broke in Illinois' favor when Richardson nailed his 3-pointer, then had a steal and assisted on Paul's 3-pointer just seconds later. Back in the lead, the Illini seemed to regain their collective composure.
Paul's 3-pointer was one of the few times he was able to break free of Roberson, who held Illinois' offensive sparkplug to 3-of-12 shooting. Roberson, who ranked second nationally in rebounding, finished with nine points and eight rebounds.
The Buffaloes were frustrated to see their big rally ultimately fall short. Colorado held Illinois to 3-of-22 shooting (13 percent) in the second half and still lost.
"We were getting stop after stop after stop and we were pushing it down their throat,'' Booker said. "We felt like we had the momentum in our hand. Give credit to Illinois.''
Illinois players said they learned how to win the tough games in the Big Ten. The Illini also have an experienced team with three senior starters, including Paul and Richardson.
"We've played in so many games where we had to come back,'' Richardson said. "We're mature players.''
Boyle is hoping to build that kind of fight in Colorado for the future.
"We played well enough to win today, we just didn't play well enough down the stretch to win,'' Boyle said. "I told them I'm proud of what they've done this year. ... They've helped put Colorado basketball on the map.''