The Heat — and Jimmy Butler — heard all the doubters. That’s one reason Miami was able to force Game 7.

Miami's Bam Adebayo celebrates after a late Jimmy Butler basket during Friday's Game 6 showdown at TD Garden.Matthew J Lee/Globe staff

After the Golden State Warriors punched their ticket to the NBA Finals, forward Draymond Green made a declaration: “We’re going to play Boston.”

Game 6 of the Eastern Conference finals had yet to tip off, but Green and countless others — including yours truly — were convinced the Celtics would advance. The Miami Heat, hampered by injuries, had looked overmatched in Games 4 and 5.

“Everybody counted us out,” center Bam Adebayo said. “Everybody thought the series was already over. That’s all the motivation we needed.”

Added forward P.J. Tucker, “Everybody picked them, even though we’re No. 1.”

P.J. Tucker and the Heat left Jaylen Brown and the Celtics reeling Friday night at TD Garden.Jim Davis/Globe Staff

The Heat had seemingly heard and read everything after Game 4, when they suffered a 20-point blowout loss, and after Game 5, when they wilted in the third quarter en route to another double-digit defeat.

Their response Friday night couldn’t have been more impressive.

With their season on the line and the odds stacked against them — Vegas had the Celtics as 8½-point favorites — the Heat marched into TD Garden and showed why they finished as the No. 1 seed in the East during the regular season. Thanks to an extraordinary performance from All-Star Jimmy Butler, Miami suddenly has life, evening the series at three games apiece.

“We’ve been saying it this entire series: It’s not finished yet,” Butler said after the 111-103 victory. “We got Game 7 at the crib and we need a win.”

As the Heat were getting ready in the locker room before Friday’s game, Tucker and Heat forward Markieff Morris knew their team needed a big performance out of Butler. They told him, “Yo, we need 50.” Butler looked back at them and didn’t say a word. He only nodded.

“I was like, ‘Oh yeah,’” Tucker recalled. “He’s about to play. He’s locked in.”

That he was. Butler’s imprint was on Game 6 from start to finish.

Despite continuing to play through right knee inflammation that flared up in Game 3, Butler put the Heat on his back, much like LeBron James did against Boston in the 2012 postseason. He scored 14 of Miami’s 29 points in the first quarter, connecting on 6 of 10 field goal attempts.

His numbers dropped off a bit in the second quarter, when he made just one of his five shots, but he was far from done. He played all but eight seconds in the second half, scoring 26 points on 9-of-14 shooting. He finished with 47, the second-most scored by a player facing elimination on the road in league history. Only Wilt Chamberlain had more.

“Jimmy just brought his competitive will tonight,” Heat coach Erik Spoelstra said. “And it was a will that did not let us lose.”

Miami’s Jimmy Butler heads back down court after hitting a big three with less than a minute left on the clock that sealed Friday's game for the Heat.Jim Davis/Globe Staff

Every time the Heat needed a bucket, Butler delivered — even with his knee still bothering him. With the game tied and just over three minutes remaining in the fourth quarter, Butler came up limping badly after driving along the baseline and almost turning over the ball.

But there was no chance he was going to leave the game — and for good reason. With less than a minute remaining and the Heat up by 4, Butler managed to knock down a ridiculous turnaround jump shot. Just 2.2 seconds remained on the shot clock when guard Max Strus inbounded the ball to Butler.

“Sometimes you just need your best player and your guy to make plays,” Spoelstra said. “He was able to do that. In those moments of truth, when we really needed it. As their defense stepped up and as [our lead] got to, like, 4 [points], 6 [points], he found a way to get us a really important bucket.”

Butler finished the fourth quarter with 17 points, making 6 of 9 shots. He alone outscored Boston’s starting lineup, who registered just 15 points on 3-of-8 shooting in the final frame.

“For him to bounce back in Game 6 and be who he is, it just speaks volumes,” Adebayo said. “Obviously, he had to take himself to a deep, dark place for that. He’s the ultimate competitor and a winner. That’s what he preaches to us.”

Butler would not let his team fold. He did it all, grabbing nine rebounds, including three on the offensive glass, and dishing eight assists. He also stole the ball four times and turned the ball over just once. Stat lines don’t get much better.

“Jimmy Butler is a great competitor,” Spoelstra said. “This defined him in a lot of different ways. His competitive will is as high as anybody that has played this game.”

As point guard Kyle Lowry put it: “It’s [expletive] incredible.”

For the most part, Butler revived all the key elements of his game: He attempted 11 free throws, he attacked the rim, and he operated comfortably in the midrange. He wasn’t afraid to let it fly from behind the arc, either, making 4 of 8 3-pointers.

Now, with Game 7 scheduled for Sunday night at FTX Arena, the only question is: Can he do it again?