ALBUQUERQUE — The much-maligned Pac-12 Conference has a surprising member carrying its banner into the first weekend of the NCAA Tournament.

At least league newbie Colorado may be a surprise to more traditional Pac-12 stalwarts — and to much of the nation, for that matter. But after holding off sixth-seeded UNLV 68-64 Thursday night at The Pit, the 11-seed Buffaloes couldn’t be feeling more confident.

And deservedly so. CU never trailed, although the Buffs let much of their 20-point lead in the second half slip away.

“NCAA Tournament games shouldn’t be easy but we didn’t handle the lead,” CU coach Tad Boyle said. “But the one thing we’ve shown all year is toughness. We did just enough.”

Colorado held off the Rebels with six clutch free throws in the final minute. The Buffs advanced to face third-seeded Baylor (29-7), which survived 68-60 against South Dakota State earlier Thursday night here.

Colorado simply out-worked UNLV for most of the night. CU’s shortest player in the game, freshman Askia Booker who is generously listed at 6-foot-1, grabbed two offensive rebounds deep in the paint, going up strong for the ball and beating 6-10, 245-pound Rebels center Brice Massamba to it.

Booker was fouled on the second offensive board and made both free throws to make it 31-18 Buffs. UNLV coach Dave Rice swung his arms in disgust.

Colorado won an NCAA Tournament game for the first time since 1997 in Winston-Salem, N.C., when the Chauncey Billups-led Buffs defeated Bob Knight-coached Indiana before losing to Dean Smith-coached North Carolina — with Smith surpassing Adolf Rupp’s then all-time victories record with Smith’s 877th.

CU was making its first NCAA Tournament appearance since the 2003 Buffs team featuring David Harrison and Michel Morandais lost in the opening round to Michigan State in St. Petersburg, Fla.

Those smiles on the faces of Colorado players said it all about winning in March Madness. How sweet it is!

“I feel our guys are playing well, playing with confidence,” CU sophomore guard Andre Roberson said of the five-game tournament run, including four in the Pac-12 tournament. “We’re going to try to keep it going. I feel we can take down Baylor.”

As it always does, UNLV came out firing 3-pointers. In this case, at the start at least, it was more like misfiring. The Rebels missed their first 7 treys before a Mike Moser swish from the right corner with 9:28 remaining in first half cut into CU’s lead at 19-10.

“We seem to be a team that can flip a switch on and off,” CU’s Carlon Brown said, referring to quick start.

Forcing the action, Colorado took a 36-25 lead into halftime, getting 12 points by the fearless freshman Booker from off the bench. CU might have gained more separation, but the Buffs committed nine turnovers in the opening 20 minutes — already more than they had averaged for an entire game in their four wins at the Pac-12 Tournament.

The usually explosive Rebels shot just 27.6 percent from the field in the first half and went 4-for-16 on 3-pointers.

But Buffs shot 45.8 percent and helped to limit UNLV to 32.4 percent shooting. When UNLV missed, Roberson was there to grab the rebound.

Averaging a double-double for the season, the 6-7 sophomore already had nine boards by halftime. Roberson finished with 12 points and 16 rebounds.

Brown, who entered the NCAA Tournament averaging 16.2 points for his past six games, turned in another top-shelf performance with 12 points and six boards. Senior forward Austin Dufault contributed 14 points and five rebounds as the Buffs outrebounded UNLV 46-33.

Junior guard Anthony Marshall led UNLV with 15 points.

Brown, a transfer from Utah, is the only member of the CU roster to have prior playing experience in the NCAA Tournament. He scored seven points for the Utes in an opening-game loss to Arizona in 2009.

Colorado and UNLV had not met in men’s basketball since 1981 — a 65-59 Buffs win in Las Vegas.

“We had a big crowd come down from Colorado and we wanted to get them excited,” said Booker, who finished with a game-high 16 points off the bench.