Oklahoma City's game Sunday against the Golden State Warriors got off to a worrying start.
Star center Chet Holmgren came down with an injury midway through the first quarter.
Holmgren went up to contest Andrew Wiggins' shot, but came down hard as the Warriors forward got the bucket.
At that point, Holmgren recorded just four rebounds in five minutes on 0-for-3 shooting but needed to be helped to the locker room.
It wasn't immediately clear if he could return to the game or would be ruled out.
It appeared he could not put any weight on his right leg while grabbing at his hip/oblique area while on the ground.
Oklahoma City has soared to an 8-1 start to the season as it looks to repeat as Western Conference champions and make a deep postseason run.
Holmgren entered Sunday's game averaging 18.2 points, 9.2 rebounds, 2.9 blocks and 2.2 assists on a 52/40/78 shooting split.