The NBA’s all-time leader in three-point baskets arrived in Miami simply looking to fit in, willing to subjugate his ego and come off the bench on a star-laden team that had already won a championship without him.

But Ray Allen ended up being far more than a complementary piece. In Heat history, he will forever be remembered as The Man Who Saved The Season.

“That was a defining moment for us — probably the biggest shot I ever hit in my career,” Allen said of his three-pointer that tied Game 6 of the Finals with 5.2 seconds left, sending it into overtime and ultimately denying the Spurs the championship.

The shot, on its own, was impressive enough.

But Heat owner Micky Arison marvels at something else — “the fact he watched the ball go into Chris [Bosh’s] hands and started to back up instinctively and stopped at exactly the right spot.

“Not a foot forward; it would have been a two. Not a foot back; he would have been out of bounds. He never looked down. Those thousands of shots in practice all culminated in that one shot. It will never be forgotten.”

As his father massaged his back in a euphoric locker room after Game 7, Allen wondered aloud: “Where would we stand if that shot didn’t go in? None of this is possible. You talk about the magnitude of the situation. That’s something I’ll think about, other people will talk about, forever.”

Allen is famously obsessive about his routine and preparation, arriving at the arena four hours before tip-off to hoist shot after shot.

‘It’s all worth it’

“For anyone who has a dream, dividends don’t pay off right away,” he said. “If you shoot 1,000 shots, you may get that shot one time. To win a game, to win a championship — it’s all worth it.”

The title also validated his decision to leave Boston, where he won a championship in 2008, to join LeBron & Co. in Miami.

“This is what I came here for,” he said. “I thought about the scenarios when I came down here and winning the championship was the ultimate goal for me. I didn’t think about anything else. It was a great leap of faith when I left. I knew I needed a change at the time.”

Before the playoffs, he said his Heat journey was “more enjoyable than I thought it would be.”

But there were difficult challenges, including coming off the bench — something he had done only eight games in 16 previous seasons.

This season, Allen would sometimes sprint down a hall during the first quarter to get his body warm before entering the game. In San Antonio during the Finals, he shot balls off a wall to get himself loose.

“Whenever you come to a team that has championship aspirations, you have to learn to play under the team’s terms,” he said. “You can’t win if you want to do it your way. That’s the sacrifice, both times winning championships, that I had to make.

“There are some things you don’t necessarily agree with, but you have to follow what the coach believes in. You have to sometimes take a back seat to another player. It’s the hardest thing in the world you’ll ever think about doing.”

Great atmosphere

His adjustment to a new role and new team was eased by a group of teammates “that welcomed me with open arms. It’s one of the best locker rooms I’ve ever been a part of. Every guy, to a man, I had a great relationship with.”

He also appreciated that the Heat coaching staff did not pigeonhole him, did not limit him to serving merely as a standstill three-pointer shooter.

The Heat also permitted him to post up, to run pick-and-rolls in transition, to snake to the basket if defenders played him tightly.

“We put Ray in more playmaking situations” than his role entailed in Boston, assistant coach David Fizdale said late in the season.

“Not a knock on their system. We’re just doing different things. It’s getting back to his Seattle days where, ‘I can do anything.’ We’ve really opened up his game, where, ‘I’m not just locked into one thing.’ ”

But with Heat teammates losing grip of their life preservers, Allen ultimately rescued them with what he does best: the corner three.

Just don’t ask Allen to pick a favorite among his two championships.

“Each one symbolizes my hard work and tears,” he said. “I think about the moments driving home, being disappointed, frustrated, upset. You cry in some moments. You get angry. I’m sure we all felt that, because it’s that hard.

“I hold them equally because there’s so much behind that one ring and trophy. Everybody talks about winning. I’m not sure everyone knows what it entails. To be part of a great situation is rare in this league.”

Allen assuredly found one.