Bulls guard Rajon Rondo suffered a fractured thumb in Game 2 against the Celtics, and he is out indefinitely.
The Bulls said the injury will not require surgery to heal.
Rondo averaged 11.5 points per game in the first two tilts of the first-round playoff series against Boston. In Game 2, Rondo had 14 assists and 5 steals.
The Bulls lead the series 2-0 and are scheduled to host the Celtics for Game 3 Friday night at the United Center. Tip-off is at 6 p.m.