A season of frustration for USC might have hit a nadir Thursday night at Galen Center.
The Trojans, who lost games in the final seconds to Stanford and Oregon this month, extended Colorado to three overtimes.
But the Trojans once again could not close for a victory.
Colorado guard Askia Booker scored a career-best 43 points, including eight in the third overtime, as the Buffaloes defeated USC, 98-94, and sent the Trojans to their fifth consecutive defeat.
The marathon loss wasted a record-tying three-point shooting performance by USC guard Katin Reinhardt, who scored a career-high 35 points.
USC fell to 9-11 overall and 1-7 in the Pac-12 Conference.
"It's not fun to lose, but I can't be upset at my team losing games like this, even though we had chances to win, because they played so hard," Coach Andy Enfield said. "I need to figure out how to win these games."
The Trojans are now two-thirds of the way through Enfield's second season.
And if they don't turn it around or get over the hump in the final 10 games, they could fall short of even equaling last season's 10-20 regular-season record, which included a 2-16 mark in conference play.
On a night when Reinhardt fulfilled his promise as a three-point shooter and forward Nikola Jovanovic scored a career-high 30 points, the Trojans had no answer for Booker. The 6-foot-2 senior from Los Angeles, who played at Price High, made 13 of 23 shots and 13 of 15 free throws, saving his most clutch shots for the third overtime.
"We were hoping he would miss a shot eventually," Enfield said, "but he didn't."
Reinhardt, a former Santa Ana Mater Dei High standout who transferred to USC from Nevada Las Vegas, made nine of 18 three-point attempts, tying the USC record for most three-pointers in a game. Several put USC in position to put away the Buffaloes.
But the third-year sophomore fouled out during the third overtime.
"We lost the game, so 35 points didn't really matter," he said. "I feel terrible. I feel like I let my team down toward the end of the game."
USC was in position to win several times, but Booker and his teammates remained relentless.
Reinhardt made four of nine three-pointers in the first half as the Trojans took — and then nearly blew — a 10-point lead. USC fell behind by 11 points midway through the second half but fought back and had a chance to win on the final possession. But with the score tied, 66-66, point guard Jordan McLaughlin missed a shot off a drive.
In the first overtime, Colorado's Xavier Johnson made a three-pointer with 30 seconds left to tie the score, 73-73. McLaughlin missed a shot from near the free throw line, sending it to a second overtime.
Reinhardt missed a potential game-winning three-pointer at the end of the second extra period and then fouled out with three minutes 41 seconds left in the third overtime.
That was all the opportunity Booker needed.
He made three shots and added two free throws to put Colorado ahead, 97-94, with 23.5 seconds left.
After a timeout, McLaughlin inbounded the ball to Jovanovic. The 6-11 sophomore passed the ball back to McLaughlin, who drove to the right side of the lane and missed a shot.