The Boston Celtics have looked elim­i­na­tion in the face four times this post­sea­son and still haven’t blinked.

Der­rick White had 24 points, in­clud­ing six 3-point­ers, and the Celtics dom­i­nat­ed the Mi­a­mi Heat 110-97 on Thurs­day night in Game 5 to ex­tend the East­ern Con­fer­ence fi­nals.

Mar­cus Smart had 23 points and five steals. Jayson Tatum and Jaylen Brown fin­ished with 21 points apiece as the Celtics won their sec­ond straight and trimmed Mi­a­mi’s se­ries lead to 3-2. The Celtics are halfway to be­com­ing the first team in NBA his­to­ry to over­come a 3-0 deficit to win a se­ries.

“We’ve got to do what­ev­er it takes to get a win,” White said.

Boston al­so sur­vived two elim­i­na­tion games in the sec­ond round against the 76ers. Teams that fell be­hind 3-0 are 0-150 all-time in se­ries.

“It just says that our backs are against the wall and we’re stick­ing to­geth­er and we’re com­pet­ing at a high lev­el to give our­selves a chance,” Celtics coach Joe Maz­zul­la said.

Game 6 is Sat­ur­day in Mi­a­mi, where the Heat will try again to be­come the sec­ond No. 8 seed to reach the NBA Fi­nals in the cur­rent for­mat, which dates to 1984.

“We’re al­ways go­ing to stay pos­i­tive, know­ing that we can and we will win the se­ries,” the Heat’s Jim­my But­ler said. “We just have to close it out at home.”

A day af­ter the Flori­da Pan­thers punched the fran­chise’s first tick­et to the Stan­ley Cup Fi­nals since 1996, for the sec­ond straight game the Heat were de­nied a spot in the NBA Fi­nals.

“One game doesn’t lead to the next game,” Heat coach Erik Spoel­stra said. “It just doesn’t mat­ter. It’s about col­lec­tive­ly prepar­ing and putting to­geth­er a great game. We’ll play much bet­ter on Sat­ur­day. That’s all we just have to fo­cus on right now.”

Dun­can Robin­son led the Heat with 18 points. Bam Ade­bayo added 16 points and eight re­bounds. But­ler had 14 points, five re­bounds and five as­sists, but sat out the fi­nal 9:47 of the game. Caleb Mar­tin fin­ished with 14 points.

It was But­ler’s low­est-scor­ing game of the play­offs. He had 16 points in Game 3, a blowout win by Mi­a­mi.

Mi­a­mi nev­er led and had 16 turnovers.

“I don’t want to say we’re sur­prised by it, but they raised their lev­el,” Robin­son said. “We’ve got to raise ours now as well.”

Boston en­tered the day just 4-5 at TD Gar­den this post­sea­son. But with a rau­cous home crowd be­hind them, the Celtics thrived on their en­er­gy.

They dove for loose balls, out­fought Mi­a­mi for re­bounds and found each oth­er for layups and dunks in tran­si­tion as they built as much as a 20-point lead in the first half.

The Heat cut in­to it, but Boston kept knock­ing down 3s and grew its edge as high as 96-72 in the fourth quar­ter.

Boston’s fans reignit­ed a “Beat the Heat!” chant that hadn’t been preva­lent since Game 1.

The Heat start­ed Kyle Lowry at point guard af­ter Gabe Vin­cent was ruled out with a sprained left an­kle ear­li­er in the day. It was Lowry’s first start since Feb. 2.

Vin­cent, the Heat’s third-lead­ing scor­er this post­sea­son, got hurt late in Mi­a­mi’s Game 4 loss when he land­ed awk­ward­ly while try­ing to save a loose ball near the Heat bench.

His pres­ence was missed as Mi­a­mi strug­gled ear­ly on the of­fen­sive end, swarmed by a Celtics’ de­fense that forced the Heat in­to 10 first-half turnovers that led to 17 Boston points. Lowry played 31 min­utes, scored five points and fin­ished with four turnovers.

“I think now it’s a se­ries,” Brown said.

TIP-INS

Heat: Were outscored 13-0 in sec­ond-half points in the open­ing 24 min­utes.

Celtics: It was the first time this sea­son that Boston had four 20-point scor­ers. ... Al Hor­ford added six points and 11 re­bounds. … The Celtics took a 61-44 edge in­to half­time. … Boston’s first turnover of the game didn’t come un­til the 8:16 mark of the sec­ond quar­ter.

FAST START

The Celtics got the fast start they had hoped for in front of their home crowd.

Smart stripped Ade­bayo on Mi­a­mi’s open­ing pos­ses­sion, ig­nit­ing a fast break and layup on the oth­er end by Tatum.

Then, with the game tied at 4, Tatum got free in the lane for a mon­strous two-hand­ed dunk. He hung on the rim af­ter­ward and con­tin­ued his cel­e­bra­tion when he land­ed, lead­ing to a tech­ni­cal foul.

It didn’t stop the Celtics’ mo­men­tum, as their first-quar­ter lead grew as high as 23-7. Boston end­ed the pe­ri­od with a 35-20 lead, punc­tu­at­ed by a 3-point­er by White at the buzzer.

Tatum had 12 points in the open­ing 12 min­utes, with the Celtics outscor­ing the Heat 21-6 from be­yond the arc. Boston hit 7 of its 12 at­tempts.

VIP WATCH

Celtics Hall of Famer Paul Pierce, NCAA pres­i­dent Char­lie Bak­er and New Eng­land Pa­tri­ots Matt Slater and Devin Mc­Cour­ty were among sev­er­al celebri­ties in the Gar­den.

BOSTON (AP) —