INDIANAPOLIS, April 29 (Ticker) -- On the verge of becoming the first team to advance, the Boston Celtics took a giant step backward.

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Ron Artest and Jermaine O'Neal combined to score the only five points in overtime as the Indiana Pacers rallied for a 93-88 victory over the Celtics, who became the first team in NBA playoff history to go scoreless in an overtime.

Boston, which entered Game 5 with a 3-1 lead in the best-of-seven series, led by as many as nine points in the fourth quarter and had an 86-81 lead with 4:27 remaining in regulation.

But the Celtics followed with an unprecedented stretch of futility, scoring only two points thereafter as both teams struggled offensively down the stretch.

"It almost seemed like the first team to score would win," Indiana guard Reggie Miller said. "It was an unbelievable game with unbelievable energy from both teams. The intensity level was so thick out there. It was a fun game to be a part of."

The Celtics forced overtime on Antoine Walker's layup with 2:01 remaining but did not score in the final seven minutes.

In overtime, Boston missed all six shots and Walker misfired on a pair of free throws with 1:58 remaining. The Celtics became the ninth team in league history to go scoreless in an overtime and first since Dec. 1, 2000.

Boston held the previous record for fewest points in overtime, managing just one in the second OT of a home loss to Charlotte on May 1, 1993.

"Both teams had trouble scoring," Walker said. "I missed two free throws that could've sealed it. It was a defensive battle in overtime."

"They defended well and took us out of our offense," Boston guard Paul Pierce said. "We couldn't get a bucket late in the fourth and in overtime and you have to give them credit. They were fighting for their lives."

The Pacers snapped a six-minute scoring drought when Artest made 1-of-2 free throws for an 89-88 lead with 68 seconds left. After Boston's Walter McCarty missed a jumper, O'Neal buried a shot from the right baseline with 32 seconds to go -- Indiana's only basket in 10 overtime attempts.

Pierce fired an airball on the Celtics' next possession and Artest, who had 26 points and 10 rebounds, sank two free throws with 12 seconds remaining as the Pacers pulled within 3-2 in the Eastern Conference first-round series.

"I thought our guys showed great courage," Indiana coach Isiah Thomas said. "Offensively we didn't shoot well, but defensively I thought our guys showed great heart. I have watched this team show resiliency the last two years."

O'Neal collected 19 points and 22 rebounds and Ron Mercer and Tim Hardaway added 13 points apiece for Indiana, who held a 55-42 rebounding advantage and grabbed 17 offensive boards leading to 17 points.

Walker finished with 21 points and Tony Delk added 19 for the Celtics, who have never blown a 3-1 lead in a best-of-seven series.

"We had a nine-point lead and we could not put them away," Pierce said. "I don't want to blame the loss on fatigue. They were desperate and we just didn't close them out."

Pierce scored eight of his 16 points in the fourth quarter and made just 5-of-21 shots for Boston, which hosts Game Six on Thursday.

"There is no pressure on us in Game Six," Boston's Eric Williams said. "We have the home court and the short turnaround shouldn't hurt us. This loss won't linger because we can get right back out there."

Pierce and J.R. Bremer ended the third quarter with consecutive 3-pointers to give the Celtics a 71-62 lead entering the fourth period. The teams traded baskets to open the final period before the Pacers went on a 15-7 run.

Artest scored six points during the spurt and Hardaway capped it with a 3-pointer to bring Indiana within 80-79 with 6:30 to go.

Pierce responded with consecutive jumpers and Boston had an 86-81 edge on Walker's layup with 4:27 left. Artest made a pair of layups around a 3-pointer from Hardaway for an 88-86 lead with 2:02 remaining.

Walker tied it on a layup and neither team scored in the final two minutes, combining to miss six shots.