‘Feels like it was always meant to be this way:’ How the Celtics escaped the Heat and set up a seismic NBA Finals

MIAMI — FTX Arena has a ceiling, but for a moment, Al Horford appeared tempted to test its limits. The Celtics forward cuffed the final rebound in the final seconds of the final game of these Eastern Conference finals, and he launched the ball toward the sky.

While it was up there, the clock officially expired, and Celtics 100, Heat 96, became permanent and real and joyful. Jayson Tatum threw his fist through the air, and a few feet away, Marcus Smart did the same. Then all three were swallowed up in a happy clump of green near midcourt.

After three failed tries over the last five years, the Celtics were on to the Finals, on to San Francisco, on to a matchup with one of this sport’s true dynasties, the Warriors. And there will soon be time to digest those real, daunting challenges. But Sunday was not the night for that.

Sunday was the night for a team that was in 11th place in January and in danger of crumbling to step back and see how far it had come.

Sunday was the night for Tatum to continue his path toward becoming a Celtics great by accepting the series MVP trophy named after one of the franchise’s greatest, Larry Bird.

Sunday was the night for Horford, who turns 36 on Friday, to reflect on what it took to get here, just one year after his lost season in Oklahoma City that ignited questions about whether he’d ever get a chance like this again.

Sunday was the night for Ime Udoka, the team’s steely first-year coach who was unbowed by early struggles and outwardly unmoved by its subsequent surge, to step back and admire this memorable run, however briefly.

“You can’t help but smile and enjoy the moment out there on the court,” Udoka said. “It’s kind of forced upon you, seeing the joy with the players.”

Make no mistake, though, it was not easy. And no one really expected it to be. You do not go through months of tumult just to hop onto an express lane here.

The Celtics led by as many as 17 points and never trailed, but suddenly, there was Heat star Jimmy Butler, after his team had roared back from a 13-point deficit in the final four minutes, rushing up the court after a missed layup by Smart with his team down by 2.

Butler, who played all 48 minutes and gave his team everything he had, is not an excellent 3-point shooter, but he is one of the most clutch players this game has seen in years. And instead of plowing toward Horford and going for a layup, he pulled up from the top of the key and let a 3-pointer fly. He went for it all.

The Celtics could smile later when they recounted the moment, because it had not harmed them. But no one was smiling at the time. They were terrified.

“Not again,” Marcus Smart recalled thinking.

“I was like, ‘Man, what the hell?’” Jaylen Brown added.

Horford pushed back into the play and contested the shot, and the ball caromed off the front of the rim and landed in Horford’s hands. It could have been disastrous for Boston. It could have gutted them. Instead, it became a footnote.

“My thought process was to go for the win,” Butler said, “which I did.”

Smart was fouled and calmly hit both free throws with 11.4 seconds left, and Max Strus missed a pair of 3-pointers as time ticked away for Miami, allowing Boston’s celebration to begin.

Jayson Tatum and Robert Williams celebrate in the aftermath of the Celtics' win.Matthew J Lee/Globe staff

It was a significant moment for Tatum, who finished with 26 points, 10 rebounds and 6 assists and carried his shiny MVP trophy to the dais for his postgame interview. Tatum said that before taking his pregame nap on Sunday, he watched old clips of his idol, former Lakers star Kobe Bryant, who played in countless games as big as this one was for Tatum.

Then Tatum took the court wearing a purple armband, in honor of Bryant, and tried his best to emulate him. But amid all of Bryant’s incredible statistics, he is remembered most as a winner, and Tatum knows he has not really won anything yet.

“I mean, [winning the East] wasn’t the goal all season, right?” Tatum said. “That was just a step in getting where we want to get to.”

And each step has seemed more challenging than the one that preceded it. The Celtics started the postseason by sweeping Kevin Durant, Kyrie Irving and the Nets in a series that was tougher than the results indicated.

Then they withstood a pair of elimination games against Giannis Antetokounmpo and the Bucks in the semifinals. Then came this series against the top-seeded Heat, in which Boston was unable to end the series in Game 6 at home, and tempted fate by going on the road in a Game 7. But the season rolls on.

“Feels like it was always meant to be this way,” Udoka said.

Now, maybe the biggest challenge of all waits. Stephen Curry, Klay Thompson and Draymond Green, who have won three NBA titles and are now on the cusp of a fourth, know better than anyone what it will take.

It will be a new experience for the Celtics, but they insist they will be ready, even if there are some things that they will have to figure out as they go.

“We’ve learned a lot over the years,” Brown said, “and now, the stage is at its brightest.”

‘Feels like it was always meant to be this way:’ How the Celtics escaped the Heat and set up a seismic NBA Finals

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