In the friendly environs of the CU Events Center, with the altitude operating as their unseen yet very productive sixth man, the Colorado Buffaloes have run some of their early opponents out of the gym.

The CU men’s basketball team will get its first taste of life without that hidden advantage this week.

After compiling the first 5-0 start in six years entirely at home, the Buffaloes head to the desert to celebrate Thanksgiving with a Thursday date against San Francisco in the first game of the Acrisure Holiday Classic in Palm Desert, California.

“We definitely need to be leaning more on our defense,” CU forward Sebastian Rancik said. “On the road we don’t have the advantage of altitude. So it’s really important for us to really concentrate on our defense and (have) that that we fall back on.”

San Francisco is coming off a 25-win season, and the Dons represent a stern first away-from-home test for the Buffs.

The Dons suffered a narrow loss at Memphis in the second game of the season but have reeled off four consecutive wins.

San Francisco is coming off a particularly impressive neutral-floor win, defeating Minnesota and first-year coach Niko Medved, the former leader at Colorado State, at the Sanford Pentagon in Sioux Falls, South Dakota. As coach Tad Boyle and the Buffs learned in past matchups against Iowa State and Iowa at the Pentagon, the locale hardly is neutral when playing a regional team like Minnesota.

“I know San Francisco is a well-coached team,” Boyle said. “They’ve got good players, so it’s not going to be easy. They beat Minnesota on a neutral court, and guess what? The Pentagon in South Dakota had a hell of a lot more Minnesota fans than San Francisco did. It wasn’t a neutral court, and they went and beat them. We know San Francisco is real and we cannot take them lightly. It’s not going to be an easy game.”

CU has scored at least 80 points in all five games — including at least 90 in the past three — and boasts lofty totals in field goal percentage (.534), 3-point percentage (.422) and assist-to-turnover ratio (2.94). However, the Buffs’ defense has been spotty at best, with three of their first five opponents finishing with a field goal percentage of at least 51%.

San Francisco is shooting .483 overall and put up a .491 mark in its win against Minnesota.

“We’ve just got to play 40 minutes. That’s what it is,” Rancik said. “We’ve had great spurts that are four or five minutes. I mean, the first media timeout (against UC Davis), they didn’t score. We’ve just got to play 40 minutes of that type of defense and we can’t let up. And that comes with concentration and communication once we get tired.

“At the end of the day, it all comes back to communication. You have to talk to your teammates, what they’re doing, and fly around. We have to demand that from each other every day at practice, and that’s the only way we’ll be able to carry it through to the game.”

CU Buffs men’s basketball vs. San Francisco Dons

TIPOFF: Thursday, noon MT, Acrisure Arena, Palm Desert, California.

TV/RADIO: CBS Sports Network/KOA 850 AM and 94.1 FM.

RECORDS: Colorado 5-0; San Francisco 5-1.

COACHES: Colorado — Tad Boyle, 16th season (317-204, 373-270 overall). San Francisco — Chris Gerlufsen, 4th season (73-36, 81-41 overall).

KEY PLAYERS: Colorado — F Sebastian Rancik, 6-11, So. (14.8 ppg, 4.4 rpg, 3.2 apg, .429 FG%, .939 FT%); G Isaiah Johnson, 6-1, Fr. (14.8 ppg, .576 FG%, .867 FT%); F Alon Michaeli, 6-9, Fr. (12.8 ppg, 4.0 rpg, .528 FG%); G Barrington Hargress, 6-1, R-Jr. (12.2 ppg, 5.6 apg, .568 FG%); F Bangot Dak, 7-0, Jr. (12.0 ppg, 7.2 rpg, .537 FG%); G Felix Kossaras, 6-6, So. (9.0 ppg, .682 FG%); C Elijah Malone, 6-10, Gr. (8.4 ppg, 5.8 rpg, .600 FG%). San Francisco — G Ryan Beasley, 5-11, Jr. (16.0 ppg, 3.0 apg, .519 FG%); F Mookie Cook, 6-6, Jr. (13.3 ppg, 5.8 rpg, .643 FG%; G Tyrone Riley IV, 6-6, So. (11.2 ppg, 5.0 rpg, .500 FG%); F David Fuchs, 6-9, Jr. (10.3 ppg, 6.5 rpg, .529 FG%).

NOTES: CU will complete the Acrisure Holiday Classic against either Nevada or former Pac-12 rival Washington on Friday. … San Francisco leads the all-time series 3-2, with CU winning the last meeting at home on Dec. 3, 2014. The most famous matchup between CU and San Francisco was on March 19, 1955, when the Dons defeated the Buffs on the way to the national championship. That San Francisco team was led by future Boston Celtics legends and eventual Hall of Famers Bill Russell and KC Jones. The 1955 NCAA Tournament date is the only previous neutral-floor matchup between the programs. … Rancik is a native of Slovakia, but he went to high school in the Los Angeles area and said some of his host family members will make the trip to Palm Desert. “My host sister and brother are coming out, so I’m really excited to see them,” Rancik said. “It’s nice to be in California and it will be amazing to have my host sister and brother at the game. They’re very close to me.” … CU went 3-4 in neutral floor games last year, going 1-2 at the Maui Invitational and 2-1 at the Big 12 tournament before losing to Villanova in Las Vegas in the season finale.