Los Angeles Clippers forward Blake Griffin suffered a left knee injury on Monday that coach Doc Rivers conceded "did not look good" but would be evaluated further.
Griffin sustained the problem in the fourth quarter of a 120-115 victory over the Los Angeles Lakers when he became entangled with Lonzo Ball and team-mate Austin Rivers.
"It didn't look good obviously, but we just have to wait and see," Doc Rivers said, per the Los Angeles Times.
"Lonzo was just trying to make a play. Lonzo knocked somebody into Blake. And there was a trigger effect. What can you say?"
No foul was called on the collision during a scrum for a loose ball with 4:43 to play.
"You could see right when it happened," Doc Rivers said. "Lonzo was just trying to make a play, but he went in. Usually when you go in like that, that hard - they call it."
Griffin remained in the game for one possession, missing a shot, then checked out and headed to the locker room.
After the game, he left without speaking to reporters but was not on crutches. Now, he and his team wait to see the extent of any damage to the knee.
"He's not in high spirits - he's down," Doc Rivers said. "Right now he's where we are at, hoping it was just a bang and that it hurt and that he'll be all right."
Griffin has been dogged by injuries throughout his eight-year NBA career, having played in 67, 35 and 61 games over the past three seasons.
Yet the Clippers signed him to a new five-year, $173million contract during this offseason.
The 8-11 Clippers' next game is on Thursday at home against the Utah Jazz, with Griffin set to undergo tests on Tuesday to determine his status.