The Boston Celtics, sparked by 26 points from Jayson Tatum, advanced to the NBA Finals by defeating Miami 100-96 on Sunday, setting up a title showdown against the Golden State Warriors.

Boston captured the winner-takes-all matchup to claim the best-of-seven Eastern Conference finals 4-3 and secure a place in the championship series, which begins Thursday in San Francisco.

"We aren't satisfied. We've still got a long way to go," Tatum said. "We know we have a tough task ahead. I'm looking forward to it."

The Celtics, who eliminated 2021 NBA champion Milwaukee in seven games, led from start to finish but had to hold off a Heat fightback in the dying minutes to reach their first NBA Finals since 2010.

"We fought through a lot of adversity," Celtics coach Ime Udoka said. "We're a resilient group. We can't ever really slam the door but we held them off.

"Now our focus is to win four more."

Boston advanced after losing the conference finals three times in the past five seasons.

"To get over the hump with this group, it means everything," Tatum said. "Not a lot of people believed in us, but it worked out."

Tatum, who also had 10 rebounds and six assists, was named the Eastern Conference Most Valuable Player.

"It was the biggest game of my career," Tatum said. "Going through those tough times helped us grow, helped us learn. They kept coming at us. We kept responding. We left it all on the floor. We got it done."

Marcus Smart and Jaylen Brown each added 24 points for Boston while Jimmy Butler led Miami with 35 points in a losing cause.

"Not good enough. I didn't do enough," Butler said. "Stats don't mean anything. I learned I have to be better and I will be better. We're going to come back better than ever."

Miami, the East's top seed, missed a chance at a second NBA Finals trip in three years and a first title since 2013.

"It's one of the worst feelings in the world to address your locker room after a game like this," Heat coach Erik Spoelstra said. "It's heartbreaking when it ends like this."

Golden State split two games with the Celtics in the regular season, winning 111-107 in December at Boston and losing 110-88 in March at home when star guard Stephen Curry was injured.

Boston hadn't been to the finals since losing 12 years ago to the Los Angeles Lakers. The Celtics haven't won the NBA crown since 2008.

The Warriors, in the NBA Finals for the sixth time in eight years, seek their fourth title in that span and the first since 2018.

"This is a great opportunity. This is what you put all the work in for your whole life," Brown said. "We've got to embrace it but also embrace the challenge.

"We're playing a team that has been there, done that before. We've got to come with our A-game."

- 'We persevered' -
Smart had six points in a 10-1 spurt by Boston for a 65-52 Celtics lead early in the third quarter, but a 7-0 Heat run soon after pulled Miami within 72-65 and the Celtics carried an 82-75 lead into the final quarter.

An 8-0 Celtics run early in the fourth quarter lifted Boston ahead 90-79, the Heat missing nine shots in a row.

"We had plenty of opportunities. We just couldn't get control of the game," Spoelstra said. "Most of the game we were grinding."

Max Strus's three-pointer closed an 11-0 run to lift Miami within 98-96 in the dying seconds, but Butler missed a late three-pointer, Smart hit two free throws and the Celtics held on.

"We've been responding all year to adversity," Brown said. "Today was the biggest test of the year, of our careers, and we got past it.

"We persevered. We got the job done."

Boston's Al Horford, a 35-year-old Dominican center, played 44 minutes and grabbed a game-high 14 rebounds to reach his first NBA Finals.

"I'm happy to be sharing this moment with these guys," Horford said. "This is a special group."

Butler, who had 24 first-half points, played all 48 minutes.

"We just couldn't afford to have him off the court," Spoelstra said.