Rajon Rondo left Wednesday's game in the third quarter with an ankle injury.
Rondo wound up playing just 25 minutes in Wednesday night's game. He finished with six points and 10 assists in what was a 98-93 victory for the Celtics.
With the quick turnaround for the Celtics, it is unclear whether Rondo will play Thursday against the Brooklyn Nets. The Celtics then have games on both Saturday and Sunday.
His absence would be a big blow for Boston, as he is the main reason the Celtics leads the NBA in assists per game. He is averaging 15.4 points and 13 assists per game so far this season.
Rondo has battled injuries in the past. He played in just 53 of 66 games or Boston last season.
Thursday's game against Brooklyn will tip off at 8:00 p.m ET.