Indiana led for all but a few minutes in the first three quarters, but Boston outscored the Pacers 29-16 in the fourth while holding them to 26 percent shooting for a 95-83 victory.
"We just kept playing defense," Celtics coach Doc Rivers said. "Then all of a sudden, our shots started falling and our defense stayed."
Boston point guard Rajon Rondo missed his fifth straight game with a sprained left ankle. The Celtics improved to 4-1 without him and maintained the best record in the Eastern Conference. The Celtics were coming off an 86-78 loss at Orlando on Christmas that ended a 14-game winning streak.
"You always want to get back on track, especially after a tough loss," Pierce said. "All of these road games are tough, no matter who you're playing because teams are comfortable in their home environment."
Glen Davis scored 14 points and former Pacer Marquis Daniels added 12 for the Celtics. They combined for eight points and two assists during the 13-2 run to start the fourth quarter that put the Celtics in control for good.
"The game turned around when they went to a big 1 guard and were able to post up T.J. and Darren," Pacers coach Jim O'Brien said. "That slowed the tempo and got them back in the game."
Allen, who scored 10 points in the fourth quarter, was impressed with Daniels.
"He did a great job tonight, not only offensively, but guarding their point guards," Allen said. "He was able to keep us under control, and he did a great job in the fourth quarter."
"We just crowded him," Rivers said. "He just missed some good shots, too. He's just a tough cover. You really want to just fight him off his spot and make him take tough shots."
The Pacers had gotten off to a promising start this season, but they now have lost consecutive home games to Memphis and Boston. Indiana had already beaten the Los Angeles Lakers and Miami this season, but the poor shooting at the end prevented the Pacers from notching another big-time win.
"When you lead good teams like we did tonight and you let them make a run at you, you're not going to be able to hang in there with them," Granger said.
Indiana led 34-25 in the second quarter before Pierce scored 10 points in two minutes to cut Indiana's lead to 39-35.
"That's just Paul," Rivers said. "He's a professional scorer. He doesn't look quick, he doesn't look athletic -- he is. But he just scores at his pace and when he gets it going, the flood gates open."
Indiana held on and led 47-45 at halftime.
The Pacers got off to a quick start in the second half as Rush made a 3-pointer and a bank shot to give the Pacers a 52-45 advantage and cause Boston to call timeout. Indiana extended the lead to double digits on a putback by Jeff Foster with just over 7 minutes left in the third quarter.
"In the third quarter, we came out lethargic, but then we started to play aggressive," Pierce said.
Boston chipped away for the next several minutes, but the Pacers held on and led 67-66 at the end of the third quarter.
Daniels scored to give the Celtics their first lead since the middle of the first quarter, then Davis followed with a jumper that gave the Celtics a 70-67 edge and led to a Pacers timeout. Boston pushed the lead out to 77-67 with starters Pierce, Kevin Garnett and Shaquille O'Neal on the bench. Indiana didn't make a field goal in the fourth quarter until Josh McRoberts scored with 7:17 left, and Boston led by at least seven points the rest of the way.
Boston had only lost two consecutive games once this season and didn't want it to happen again.
"The winning track is always a good track to be on," Pierce said. "You don't want to be on that train when you're losing and you're going downhill fast. I don't think we've been playing great. We can play a lot better."
The Pacers shot 53 percent in the first quarter and led 26-19 at the end of the period. ... Colts receiver Reggie Wayne, named Tuesday as a starter in the NFL Pro Bowl, attended the game. ... Pacers G Mike Dunleavy and Celtics G Nate Robinson collided in the third quarter. Dunleavy ran straight to the locker room holding his face and ended up getting stitches to close a laceration above his right eye. Robinson was cut above the left eye and was to get stitches after the game. ... O'Neal fouled out with nine points and two rebounds.
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