Boston Celtics secure 3-1 lead over Atlanta Hawks as Jayson Tatum and Jaylen Brown flourish

Jaylen Brown and Jayson Tatum each scored 31 points as the Boston Celtics led nearly the entire way, holding off the Atlanta Hawks for a 129-121 victory Sunday night and commanding 3-1 lead in the opening-round playoff series.

The Celtics can deliver the clincher Tuesday night when the series returns to Boston for Game 5.

Tatum and Brown combined to score Boston’s final 16 points.

Brown, who has been wearing a protective mask after sustaining facial contusions in February, took off the device after making only 1 of 7 shots. He went 11 of 15 the rest of the way.

Boston never trailed after grabbing a 4-3 lead on Derrick White’s basket just over a minute into the game.

The Boston Celtics defeated the Atlanta Hawks 129-121 to take a 3-1 lead in their playoff series

Jaylen Brown (L) and Jayson Tatum (R) both recorded 31 points to lead the Celtics in scoring

Trae Young led the way for the Hawks with 35 points on 11-26 shooting in the losing effort 

Tatum delivered a huge 3-pointer off a loose ball with two minutes remaining, pushing the Celtics to a 118-106 lead.

After Trae Young swished a long 3 to provide Atlanta’s last gasp, Brown knocked one down from beyond the arc seal it for the Celtics.

Marcus Smart added 19 points and Derrick White 18 for the Celtics.

Young had another big game for Atlanta with 35 points, but it wasn’t enough. De’Andre Hunter chipped in with 27 and DeJounte Murray had 23.

Hunter ripped off eight straight points, including a couple of 3s, and then delivered a thunderous dunk that brought the Hawks within 53-49.

But Boston closed the first half on a 12-4 spurt, capped by Smart’s 3-pointer that sent the visitors to the locker room with a 65-53 lead and sapped a lot of energy from the home crowd.

The Celtics tenaciously protected their edge throughout the third period.

Young hit a long 3-pointer that brought the Hawks within three, but Boston got the last shot and put the ball in Smart’s hands. The Celtics cleared the middle of the court so he could blow by Bogdan Bogdanovic, laying it in for a 92-87 lead heading to the final quarter.

Smart was in the Celtics lineup and looked just fine after a hard fall near the end of Game 3.

He landed on his tailbone while battling for a rebound, prompting Boston to list him as a game-time decision. But coach Joe Mazzulla declared his guard ‘good to go’ well ahead of tipoff.

 Robert Williams III (44) reacts after diving for the ball against Hawks forward Saddiq Bey (41)