BOSTON — Isaiah Thomas used to imagine what it would be like to play in a Game 7 as he watched some of the NBA’s biggest names cement their legacies on the league’s biggest stage.

The Celtics’ All-Star will get his first chance to do the same on Monday night when Boston hosts the Washington Wizards, with a trip to the Eastern Conference finals at stake.

While Thomas is anxious for the opportunity, one thing he says he won’t be is nervous.

“I don’t believe in pressure,” Thomas said. “I’ve worked too hard to be scared of any type of pressure.”

Neither is a Washington team that pulled out a one-point win Friday in Game 6, becoming the first home team to stave off elimination on its home floor this postseason.

Home teams had previously been 0-10 in elimination games during the 2017 playoffs.

“A lot of guys doubted us winning (Game 6) at home,” Wizards point guard John Wall said. “The last two years we were in the playoffs, we lost Game 6 here, (but) we just had a lot of heart.”

Monday’s winner earns a matchup with the defending champion Cleveland Cavaliers, who have been awaiting an opponent since finishing a sweep of Toronto on May 7.

For the Celtics, an opportunity to face the Cavs would validate their No. 1 seed.

It would also be the Celtics’ first trip to the conference finals since 2012, the last run made by Boston’s since-departed Big Three of Kevin Garnett, Paul Pierce and Ray Allen.

In Washington, the drought has been much longer.

The Wizards haven’t been past the second round since 1979, when the then-Bullets beat the Spurs to advance to the NBA finals. That series was Washington’s last time in a Game 7.

Game 7 will also – at least for now – settle the score between teams that haven’t hidden their dislike for one another. The Wizards wore all-black to a regular-season matchup in January before soundly beating the Celtics.

Several Boston players showed up wearing black for Game 6, but the Celtics weren’t able to end the Wizards’ season.

Washington’s Ian Mahinmi, who was part of the 2014 Indiana Pacers’ team that eliminated Washington in the East semifinals, said Wall and Bradley Beal have matured a lot since then.

“Now, those guys are not babies anymore,” Mahinmi said. “(They’re) closers. (They’re) proven closers.”

Thomas has gotten mental advice this postseason from Kobe Bryant and most recently Paul Pierce after the Wizards evened the series in Game 4.

Pierce’s advice was ringing in his ears Sunday.

“Winning’s hard. It’s not for everybody,” Thomas recalled Pierce telling him. “If it was easy, it would be.”

NEED TO KNOW: No franchise has been in more Game 7s than the Celtics. Boston is 21-8 Game 7s, while Washington is 6-3. Home teams are 101-26 all time.

KEEP AN EYE ON: The scoring production of Wall and Beal. The Wizards are 6-2 in the playoffs when Wall and Beal combine for 50 or more points. They combined for 59 points in Game 6.

INJURY UPDATE: Mahinmi said he has “good and bad days” on the left calf that kept him out the first two games of the series, but said plans to play in Game 7.

PRESSURE IS ON: Thomas and Wall. Thomas scored more than 20 points in Game 6 for the first time since his 53-point effort in Game 2.

He was mostly contained in Games 3 through 5 as Washington sent multiple defenders at him.

The Celtics will need him to have a big night to stunt Washington’s momentum.

The same is true for Wall, who said he would think of this season as a disappointment if the Wizards come up short.