ESPN and the San Antonio Express-News reported that the 21-year-old French star did not make the trip to Indianapolis and will receive more care in Texas despite an MRI on Thursday that showed no ligament damage.
Wembanyama, who turns 22 on Sunday, will be listed as questionable for Saturday's home game against Portland, ESPN reported. The next Spurs game is scheduled for Tuesday in Memphis.
Wembanyama was injured in San Antonio's 134-132 home victory over New York on Wednesday.
The Spurs are 24-9 and rank second in the Western Conference, 4.5 games back of NBA-best Oklahoma City, and third overall in the league behind the Thunder and Detroit.
Wembanyama is averaging 24.3 points, 11.7 rebounds, 3.4 assists, and 2.9 blocked shots a game in 21 appearances this season.