Boston learned Friday that reserve Jared Sullinger would miss the rest of the season due to back surgery, but the Celtics' bench players responded by scoring 43 points.
Orlando reduced an 11-point halftime deficit to three late in the third period, but by the time that quarter was over the Celtics had rebuilt a 13-point cushion and they were not threatened in the fourth quarter.
Paul Pierce had 14 points, 11 rebounds and seven assists for Boston, which won its third straight game to get back to the breakeven mark. They have won all three without point guard Rajon Rondo.
Orlando was also shorthanded -- missing Glen Davis with a broken foot and Arron Afflalo with a strained calf. J.J. Redick scored 15 points to lead Orlando.