Jimmy Butler had to leave the Minnesota Timberwolves' matchup against the Houston 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.
He was unable to put any weight on his right knee when leaving the court. According to Yahoo Sports, X-rays on his knee were negative.
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. He will undergo an MRI on Saturday.