Marcus Smart left Sunday's game vs. the Knicks after suffering an injury in the third quarter.
The Boston Celtics guard exited after taking an elbow to the oblique area.
Watch the play below:
The Celtics ruled Smart out for the rest of the game shortly thereafter:
This post will be updated when more information is available.
Don't miss NBC Sports Boston's coverage of Celtics-Heat, which tips off Wednesday at 7 p.m. with Celtics Pregame Live, and then Tommy & Mike have the call at 7:30 p.m. You can also stream the game on the MyTeams App.