The veteran was held to just nine minutes of action in Friday's win over the Orlando Magic and didn't return after suffering the injury while playing in just under 10 minutes. Anthony said after the game he wanted to play Saturday, per Bleacher Report's Sean Highkin, but the team is apparently being more cautious.
Anthony has been a reliable player for Portland since signing in mid-November.
The 35-year-old is averaging 16.0 points and 6.2 rebounds per game in 15 appearances this year, giving the Blazers some frontcourt balance to pair with star guards Damian Lillard and CJ McCollum.
He was named the Western Conference Player of the Week in early December after his hot start, while his 41.7 percent efficiency from three-point range is also better than many expected.
The 10-time All-Star spent over a year away from the sport while remaining unsigned following his short stint with the Houston Rockets in 2018-19, but he is showing that he can still help a playoff contender.
However, the injury will help highlight Portland's lack of depth at forward. Anthony Tolliver should see extra playing time Saturday, especially with Mario Hezonja questionable with a back injury.