LOS ANGELES — With two top-15 teams on the schedule this week in a four-day span, the Colorado men's basketball team understood it would get a revealing test to see just how the Buffaloes stack up against the best in the Pac-12 Conference as well as the nation.

Following the first of those challenges on Wednesday night at No. 5 UCLA, it seems the Buffs are close. But they aren't quite there yet.

CU refused to go away quietly after the Bruins looked as if they might run the Buffs out of the gym late in the first half. Yet this time another second-half rally by CU wasn't enough, as the fifth-ranked Bruins held off their guests to send the Buffs back to Boulder with a 73-61 defeat.

CU (6-2, 1-1 Pac-12) won't have much time to dwell on the loss ahead of a visit from No. 13 Tennessee on Saturday.

A jumper from the free throw line by CU senior guard Elijah Parquet kept the Buffs within 22-16 of the Bruins with 7 minutes, 30 seconds left in the first half, but things quickly unraveled from there. CU committed four turnovers over the next three minutes, aiding an 11-0 run by the Bruins that gave the hosts a 17-point lead late in the first half and a 39-23 advantage at halftime.

So far this season the Buffs have been a second-half team, and on Wednesday they immediately made noise after halftime, scoring the first six points of the second half while intensifying the defensive pressure.

CU shot just .370 in the first half but found the mark after the break, eventually cutting UCLA's lead to four points on a pair of free throws from Jabari Walker with 9:34 to play. But the Bruins scored the next six points in what became a 9-2 run, and the Buffs didn't get the deficit under 10 the rest of the way. Amid that 9-2 run, Buffs senior Evan Battey fouled out with 6:30 to go after recording just four points with two rebounds.

Walker posted 22 points and 11 rebounds for his fourth consecutive double-double. CU was just 5-for-21 on 3-pointers while the Bruins went 7-for-16.

No. 5 UCLA 73, Colorado 61

COLORADO (6-1, 1-1 Pac-12)

Battey 2-7 0-1 4, Walker 7-11 6-8 22, da Silva 2-4 0-0 4, Barthelemy 1-5 0-0 2, Parquet 4-8 2-2 11, Clifford 3-6 1-2 9, Simpson 3-9 0-0 6, Lovering 0-0 1-2 1, O'Brien 1-3 0-0 2, Hammond 0-1 0-0 0. Totals 23-54 10-15 61.

UCLA (7-1, 1-0)

Johnson 5-6 2-6 12, Bernard 3-9 2-2 10, Campbell 8-16 1-2 21, Juzang 6-15 2-2 15, Jaquez 0-0 0-0 0, Clark 2-3 0-0 4, Singleton 2-5 0-0 4, Nwuba 1-2 0-0 2, Watson 0-2 3-4 3, Kyman 0-0 2-2 2. Totals 27-58 12-18 73.

Halftime – UCLA 39-23. 3-Point Goals – Colorado 5-21 (Clifford 2-4, Walker 2-4, Parquet 1-4, Battey 0-1, Hammond 0-1, O'Brien 0-1, da Silva 0-1, Barthelemy 0-2, Simpson 0-3), UCLA 7-16 (Campbell 4-7, Bernard 2-4, Juzang 1-3, Singleton 0-2). Fouled Out – Battey. Rebounds – Colorado 26 (Walker 11), UCLA 34 (Johnson 10). Assists – Colorado 11 (Barthelemy 4), UCLA 15 (Juzang 6). Total Fouls – Colorado 18, UCLA 18.