Jimmy Butler's MRI came back negative for a torn ACL, but it did reveal a meniscal injury, the team announced Saturday.
The team did not reveal a timetable for Butler's return, but Yahoo Sports reported he is expected to have surgery and will miss four to six weeks.
The Timberwolves' star forward had to leave Minnesota's matchup against the Rockets in the third quarter with an apparent right-knee injury.
Butler hurt himself on a play where he came down after a rebound on Rockets center Nene. He managed to move a little bit after the play, but after taking a couple of steps he collapsed to the floor in obvious pain.
Butler was named an All-Star this season as he was averaging 22.4 points and 5.5 rebounds per game. He had 10 points and five rebounds Friday.