BOSTON — Before the Boston Celtics took the floor without their biggest star on a night they had to win, Joe Mazzulla implored his players to just pour everything they had into winning one game.

They did, and the defending NBA champion earned another chance to extend its season.

Derrick White had 34 points, including seven 3-pointers, to lead the Celtics to a 127-102 Game 5 win over the New York Knicks on Wednesday night that kept them alive in the Eastern Conference semifinals.

"We did what was necessary to do what we needed to take it back to New York," Mazzulla said. "You don't get to pick the tests that you have, you pick how you respond to them.

"Whatever it is that we have to go through, there's no bunch of people I'd rather do it with than the guys in that locker room," Mazzulla added. "It's that simple.

"They made enough plays to win, and they gave us another chance to play.

"You never want to be without any of your players, especially one of your best ones. But regardless of who's out, each guy steps up and plays a role."

The Celtics connected on 22 3-pointers to post their first home victory of the series and first without Jayson Tatum following his season-ending Achilles tendon injury.

"Losing JT is tough," White said. "But we've got a lot of guys that are highly competitive, and we didn't want the season to end tonight."

The Knicks will try again to win the series in New York on Friday. If the Celtics win, they will return to Boston for Game 7 on Monday.

Jaylen Brown added 26 points and 12 assists. Payton Pritchard had 17 points and five 3-pointers. Luke Kornet finished with 10 points, nine rebounds and seven blocks. He started the second half for Kristaps Porzingis, who played just 12 minutes. Mazzulla said Porzingis was having trouble breathing, as he continues to deal with a lingering viral illness.

The Celtics are looking to become just the 14th team in NBA history to come back from a 3-1 deficit in 294 attempts.

Josh Hart led the Knicks with 24 points, despite briefly leaving the game late in the first quarter to close a bloody gash over his eye after being inadvertently struck by an elbow.

Jalen Brunson added 22 points, before fouling out with 7:19 to play in the game.

Knicks coach Tom Thibodeau said his team's failure to build on a solid start that saw them lead by nine points in the second quarter had proven costly.

"We didn't play tough with the lead in the second quarter. Then, we came out for the third quarter and didn't play well — you can't afford to do that," Thibodeau said.

"That we didn't play for 48 minutes," said Thibodeau when asked what stood out Wednesday." (You) can't afford to do that."

Boston closed the third quarter on a 23-9 run and took a 91-76 lead to the fourth. Brunson spent the final 2:45 of the third on the bench after picking up his fifth foul.

"They came out with a sense of urgency that we need," Brunson said.

The Celtics kept it going in the final period, pushing their lead as high as 28 points.

The game was highly physical throughout, and included a brief face-to-face skirmish between Hart and Brown.

That energy carried over offensively. The Celtics came out hot, getting five 3s from White and 12 total in the opening 24 minutes.

"We've got to play desperate. I don't think we did that," Knicks guard Mikal Bridges said.

But, the Knicks held as much as a nine-point lead, connecting on eight 3s of their own and getting 10 second-chance points. Mitchell Robinson also converted on all four of his free throw attempts in the first half, nullifying the series-long intentional foul strategy Boston employed on him.

Agencies