Reserves Nate Robinson and Glen Davis scored 15 points for Boston, which played its third game in four nights.
Roy Hibbert scored 23, and Troy Murphy had 17 points and 10 rebounds for the Pacers, who have won just once in their last six games, twice in their last 10 and three times in their last 15. Starting point guard T.J. Ford left with 7:33 remaining in the first quarter due to a sore left groin and did not return.
Indiana has allowed at least 100 points in 10 of its last 14 games.
The Celtics led by six after one and by 20 at halftime, pulling away with an 11-2 run midway through the second quarter that turned an 11-point lead into a 62-42 blowout. They led by as many as 24 in the third quarter and 25 in the fourth; the Pacers never got closer than 16 points in the second half.
Kevin Garnett, who had nine points and six rebounds, came out with four minutes left in the third. Pierce came out 100 seconds later, and Rondo and Ray Allen went to the bench with 30 seconds left in the third.
They stayed there for the fourth quarter because they weren't needed.
It was a much-needed rest for the starters, who have struggled through six games in 11 nights and are just 18-18 since beating the Orlando Magic on Christmas Day.
Notes
The Celtics honored members of the military with their "Seats for Soldiers" night. The game was also broadcast for soldiers in Iraq, who were shown on the video board. … With 618 assists for the season, Rondo passed John Havlicek and tied Tiny Archibald for the sixth-best season by a Celtic. Rondo, who already holds the No. 4 mark with 659 last year, needs 716 to pass Bob Cousy for the best in franchise history. … The Pacers fell to 7-28 on the road.