As the Pacers cut Boston's lead to two in the third quarter, Pierce put the team on his back, netting 17 of his 28 points in the stanza as the Celtics took down Indiana, 94-87, for their fourth straight win.
"We had unbelievable energy," Celtics head coach Doc Rivers said. "We thought the key was to force them into playing vs. our half court defense. Thought we did that."
Pierce also added 10 rebounds and eight assists for the Celtics.
Rondo sat out his fifth consecutive game due to a wrist injury, while Allen missed his third straight contest with a jammed left ankle.
But Pierce has really stepped up in their absence, averaging 23.4 points, 8.2 assists and 6.4 rebounds over his last five outings -- including Friday night's game.
Danny Granger netted 21 points to lead the Pacers, who went 1-of-19 from beyond the arc.
Indiana, which came into Friday's game averaging 12.8 offensive rebounds per game, outrebounded the Celtics by just a 10-9 margin on the offensive glass.
"They're the number one offensive rebounding team in the league. We concentrated on that and got some second chance points ourselves," Pierce said.
An 8-2 Pacers spurt to start the second half, capped by David West's jumper, trimmed Boston's lead to 44-42.
But Pierce poured in nine points as the Celtics countered with a 15-4 run to increase the advantage back to double-digits, 57-46, midway through the third.
Boston took a 71-61 lead into the fourth.
The Celtics led by as many as 16 in the final stanza as the Pacers were unable to rally down the stretch.
Chris Wilcox had six points as Boston led 23-17 after the first quarter. The Pacers turned the ball over six times in the opening stanza.
Boston used a 10-0 run in between the first and second quarters to take a 27-17 advantage with 10:51 remaining in the half. Boston's bench provided the spark, going 4-for-4 from the field during the spurt.
West nailed a jumper at the first-half buzzer to cut Indiana's deficit to 42-34 heading into the locker room. Boston held Indiana to just 30 percent shooting from the floor in the opening half.
The Celtics snapped a three-game losing streak against the Pacers...Wilcox finished with 14 points and Kevin Garnett added 13 points and eight rebounds for Boston...Boston outrebounded Indiana 45-42.