PORTLAND, Ore. -- San Antonio Spurs coach Gregg Popovich said Friday that Victor Wembanyama will sit out back-to-backs for a couple of weeks and remain on a minutes restriction, as the team continues to be cautious with the rookie center's ankle injury.

Wembanyama landed on the foot of a Mavericks ball boy during his pregame warmup Dec. 23, two games after being sidelined with right ankle soreness. The team sat him that night against Dallas as a precaution, citing a right ankle sprain.

Wembanyama returned to action Tuesday but is out for Friday night's game against the Trail Blazers, the second night of a back-to-back with Portland. The Spurs officially listed Wembanyama as out due to rest, but are trying to prevent any further injuries to his ankle.

Popovich said Wembanyama's absence Friday was "mandated" by the team's medical staff.

"He's got a minutes restriction and he can't play back-to-backs for a couple of weeks until they take another picture and check out his foot again," Popovich said.

The Spurs have three back-to-backs next month: home vs. Charlotte and Chicago (Jan. 12-13), at Charlotte and Washington (Jan. 19-20), and then home against Portland and Minnesota (Jan. 26-27).

On Thursday against Portland, Wembanyama had 30 points, 6 rebounds, 6 assists and 7 blocks in 24 minutes. He became the third rookie with 30 points, 5 assists and 5 blocks in a game, joining Spurs Hall of Famers David Robinson and Tim Duncan.

He also became the first player -- rookie or otherwise -- to have 25 points, 5 assists and 5 blocks in a game while playing fewer than 25 minutes.

"When we sat him in Dallas, he wasn't happy, but I'm glad he wasn't happy," Popovich said. "He's a competitor. All these guys at this level, they didn't get here by being noncompetitive. So, he'd rather be playing. It frustrates him more than anything."

After returning to the lineup Tuesday, Wembanyama said he trusts the San Antonio medical staff completely.

"We communicate a lot with the medical staff and I've made it clear that I want them to sit me out," Wembanyama said. "I'm going to trust them if they want me to sit out, but only if I really need to. If they force me pretty much. If it was up to me, I'd play every game. But I respect my role. They're professionals. I'm a professional. I try to do my job the best I can."