The task was much tougher than expected, but the Boston Celtics walked out of Game 4 Saturday night with a 3-0 lead over the shorthanded Indiana Pacers.

Led by Jayson Tatum with 36 points, the East's top seed erased an 18-point deficit to break the Pacers' hearts with a 114-111 win in the Eastern Conference finals. Game 4 is scheduled for Monday at 8 p.m. ET.

No team has come back from being down 3-0 in a series in NBA history.

The Pacers entered the game without Tyrese Haliburton, who exited Game 3 with a hamstring injury and was ruled out hours before Game 4. He was capably replaced by Andrew Nembhard, who posted a Haliburton-esque night with a career-high 32 points on 12-of-21 shooting and nine assists.

That, combined with 20-plus points from Pascal Siakam, Myles Turner and bench hero T.J. McConnell, looked like it would be enough.

Instead, the Celtics steadily chipped away throughout the second half. Tatum took over, hitting 12-of-23 shots to go along with 10 rebounds, eight assists, two blocks and zero turnovers. They had the lead down to five points early in the fourth quarter, down to three not long after that and down to two with 1:12 left.

Jrue Holiday finally put them over the top with an and-1 in the final minute, finishing through contact by Siakam.

Holiday, who was questionable for the game due to an illness, haunted the Pacers again on what could have been a game-winning possession, stripping Nembhard for a steal with four seconds left.

The Gainbridge Fieldhouse, which had been exuberant for much of the game, was silent as officials reviewed whether a clear path foul was committed against Holiday after the steal. The review went the Pacers' way, but Holiday still got two free throws, which he made to put the Celtics up three points with 1.7 seconds left.

That still gave Indiana one last chance to tie a game they led by double digits for much of two quarters. It opted to run what looked like a football play, which succeeded in getting a running Nembhard the ball at the perimeter, but his buzzer-beating attempt clanked away to end the game.

Pacers head coach Rick Carlisle was irate as the Celtics celebrated due to some contact on Nembhard, but no whistle came.

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Al Horford makes personal and NBA playoff history

As much as the Pacers can lament the loss of Haliburton, the Celtics have been playing the entire series without starting center Kristaps Porziņģis. The reason they aren't complaining is the play of Al Horford.

The 37-year-old veteran was again a difference-maker in the starting lineup, scoring 23 points with 7-of-12 3-point shooting. That number is both a career high for Horford in his 17th NBA season and enough to make him the oldest player in NBA history to make seven 3-pointers in a playoff game.

Porziņģis is reportedly trending toward a return as soon as Game 4, but Horford has given the Celtics the luxury of not needing him and potentially giving the Latvian plenty of rest before the NBA Finals.

Andrew Nembhard really was that good

Nembhard was close to a signature playoff moment on that last 3-point attempt. What happened Saturday still stands out as perhaps the most impressive night of his basketball career.

Nembhard's 32 points weren't just a playoff best or a season high for him. They're the most points he's scored in a game in his NBA and college careers. And he did it against the Celtics, who boast one of the best defensive backcourts in the NBA with Holiday and Derrick White, plus Tatum and Jaylen Brown around the perimeter.

Andrew Nembhard

SG - IND - #2

5/25/2024 v. BOS

32

Pts

4

Reb

9

Ast

0

Stl

39:24

Min

Nembhard was a second-round pick in 2022, quickly played his way into the Pacers' rotation and stayed there as the Pacers rose in the Eastern Conference ranks this season. With Haliburton out, Indiana moved Ben Sheppard into the starting lineup and handed the primary ball-handling duties to Nembhard.

Game 3 showed Nembhard's potential could still be higher than anyone expected, though that's not much consolation as the Pacers face the likely end to their season.