INDIANAPOLIS – The last time they played at Gainbridge Fieldhouse, many of the Celtics celebrated afterward by drinking beer in the visitors' locker room. On Wednesday, Boston's players returned to the building where they had secured their place in the NBA Finals and had the more sobering experience of failing to mount a major comeback.

Jaylen Brown watched his team's 135-132 overtime loss to the Pacers by sitting in front of his locker in silence for several minutes. Brown, who had a scowl on his face the entire time, didn't immediately accept defeat. Such violent reactions are often reserved for bigger games, but his missed 3-pointer with five seconds left could have tied the game, and he blamed himself for more than just that final shot.

“It’s just that our energy was lacking,” Brown said. “A lot of it was on me.”

Shortly after Brown pointed the finger at himself, Jayson Tatum did the same. Like Brown, he missed a crucial shot in overtime, but Tatum was more frustrated with the approach he took on the court. Although he scored 37 points, including a 3-pointer to force overtime, he believed he had let his team down.

“I just didn’t like the way I started the game,” Tatum said. “I feel like I'm setting the tone negatively. My energy wasn't where it should be. And I just felt like that had a domino effect. We were a step behind on offense and defense, so I take a lot of the blame for that. I just wanted to keep going in the second half.”

The Celtics almost pulled off a stunning escape, but Pascal Siakam was able to score the final five points of the game. After Siakam tied the score at 132-132 with 36 seconds left, Boston looked for a quick shot to secure a two-on-one chance, but Tatum missed a stepback three-pointer that would have given his team the lead . Siakam then hit a three-pointer that proved to be the game-winning basket after Brown shot a long jumper over Bennedict Mathurin on the Celtics' final possession.

Brown relished the opportunity on the final shot but said his miss was a reflection of his style of play.

“I just didn’t have any legs under me,” Brown said. “I thought it looked good. I just didn't have my legs under me all night. No explosion, no explosion, and I think that’s what cost us.”

final pic.twitter.com/3WhmAo3VuD

— Boston Celtics (@celtics) October 31, 2024

Boston's two All-Stars were hard on themselves after their first loss of the season. Although each of them could have regretted big mistakes in overtime, they seemed more annoyed that they weren't playing at their usual strength early in the game could. While the Celtics fell behind by as many as 24 points, they shot just 6 of 15 from beyond the arc in the first half, including 2 of 7 from that distance in the second quarter. Her missed layups sparked a Pacers offense that had struggled in the team's first four games.

“We put ourselves in a hole early in the game because of not converting open looks,” Brown said, “not being physical enough on drives and finishing at the rim. “And a lot of that was on me, I have to to get better for my boys.”

The Pacers lost three of their first four games this season. Their offense, which barely slowed down last season, finished an ugly 23rd. Rick Carlisle said they were still trying to regain the lead that took them to the Eastern Conference finals and caused problems for Boston in that series. Although the Celtics won in one game, the Pacers tested them as much as any other playoff opponent and almost won a few games. Carlisle suggested his team struggled to carry that experience over into this season.

“Sometimes it’s hard to remember how hard things were,” Carlisle said. “So this is where we are now.”

The Pacers appeared to be back in playoff shape on Wednesday. Joe Mazzulla praised them for outplaying his group for most of the game and said his team was “a step behind in everything.”

“I thought their speed, their tempo, they were just a step ahead of us,” Mazzulla said. “It wasn't our best evening. I thought we missed a lot of layups. I thought we had a couple of two-handed rebounds that we didn't get because we knocked them down. So we just didn't play our best and Indiana played great. But there are two things, right? You can focus on that and you can focus on the fact that we just stuck with it. We stayed in it.”

Mazzulla could have cleared his bench at various points in the second half because the game was so one-sided, but he said he never thought about it. Instead, in a sign that the Celtics would do everything they could to overcome the Pacers' lead, Tatum started the fourth quarter after playing the entire third. The Celtics still hadn't gained any ground on Indiana at the start of the fourth period. Shortly after Tatum returned for his final stint with 5:17 left, Boston still trailed by 16 points.

The comeback was abrupt. Derrick White drilled a 3-pointer. Brown drove in for a dunk. Neemias Queta, who finished the game in place of Al Horford, rewarded Mazzula's trust by grabbing four offensive rebounds in 14 minutes. With less than two minutes left, White scored another basket and then intercepted the pass that followed. He set up Tatum to hit two free throws that put the Celtics up 122-117. On the Pacers' ensuing possession, Brown grabbed Mathurin's pocket and ran for a break bucket. The Celtics were still down by three points in the final seconds, but Tatum scored the equalizer with three points.

JT SEND US OVERTIME pic.twitter.com/pKOI3maNV7

— Boston Celtics (@celtics) October 31, 2024

“They didn’t fit together in transition,” Tatum said. “I saw they had Haliburton with me. I understand that this is probably not the matchup they wanted. Payton (Pritchard) just threw it to me quickly. I thought they were going to commit a foul, so I just wanted to take a quick shot. We still had some time in case I missed getting the rebound or whatever.”

After Haliburton missed a long run at the end of regulation, Tatum celebrated with a shout toward the Boston bench. His team, which had looked dead just minutes before, had flown from the grave by overcoming a 19-point deficit with 7:27 left in the final. After all the Celtics' mistakes in the first three quarters, the chance at overtime must have felt like a gift.

From then on they couldn't pull out the win.

“There are two things to focus on,” Mazzulla said. “We have to make sure we get out without being half a step behind. But you see what we are capable of from top to bottom. And the boys fought, so that was good.”

Despite the late fight, Tatum and Brown knew one good quarter wasn't enough.

“It starts with us,” Tatum said. “We just have to get better with our energy and try to execute and make the right plays. And not just score. We have to be able to get stops, we have to be able to recover, we have to be able to get guys ahead. Playing with the energy is contagious. And it kind of starts with us.”

(Photo of Isaiah Jackson blocking a shot from Jaylen Brown in the second half on Wednesday night: Marc Lebryk / Imagn Images)