The 2023-24 Celtics were one of the best 3-point shooting teams in NBA history. But for much of Sunday night’s game, their threes simply weren’t falling.

More than halfway through the fourth quarter of Game 2 of the NBA Finals, Boston’s shooting percentage from deep sat at just over 20 percent. It was one of the worst outside shooting performances in a mostly dominant postseason for Joe Mazzulla’s squad.

Then, with just over four minutes remaining, Jrue Holiday and Derrick White drilled threes on back-to-back possessions to give Boston a 14-point lead and effectively put the Mavericks away.

Dallas staged one final rally, but Jaylen Brown followed up a White block with a game-clinching layup in the final minute to give the Celtics a 105-98 victory and a 2-0 lead in the best-of-seven Finals.

Game 3 is Wednesday night in Dallas.

Holiday was the star of the game for Boston, scoring 26 points on hyper-efficient 11-of-14 shooting while grabbing 11 rebounds. Brown finished 21 points, and White had 18, with each adding three steals.

The Celtics won despite a rough shooting performance by superstar Jayson Tatum, who went 6-for-22 and 1-for-7 from three to finish with 18 points. He impacted the game in other ways, though, dishing out 12 assists and grabbing nine rebounds to fall just short of a triple-double.

Doncic had 32 points, 11 rebounds and 11 assists to lead the Mavericks, but he scored just nine in the second half and turned the ball over eight times. Kyrie Irving finished with 16 points and six assists.

Ice-cold Celtics shooting helped the Mavericks open an early seven-point lead. But after Jason Kidd unsuccessfully challenged a foul on a Derrick White drive, Boston began to claw back. Tenacious defense by Jaylen Brown and a couple of impactful early shifts from Kristaps Porzingis helped the Celtics pull even with a minute remaining in the first quarter.

Boston trailed 28-25 after one despite missing its first eight 3-point attempts. Al Horford finally ended that drought by hitting a three with five seconds remaining in the quarter. The Mavericks didn’t help themselves by making just four of their nine first-quarter free throws, and they got next to nothing from their role players.

Both of those trends continued in the second quarter. At halftime, Doncic had 23 points on 9-of-13 shooting. Irving had 10 (5-for-10). The rest of Dallas’ roster had 18 total and was 7-for-20 from the floor, including 1-for-7 from three. The Celtics led 54-51 at the break despite an ugly 2-for-10 shooting performance from Tatum.

Tatum was an effective facilitator, though, dishing out eight first-half assists. Five of those went to Holiday, the Finals-tested veteran who was one of Boston’s best players in the conference finals.

Holiday scored 17 first-half points, mostly off savvy moves in the paint and strong finishes at the rim. He was 5-for-5 inside the restricted area and closed out the half with a corner three off a Tatum drive-and-kick.

Porzingis, who admitted Saturday that he’s still on a minutes restriction after missing five weeks with a calf strain, made an immediate impact for the second straight game. In his 13 first-half minutes off the bench, he had 10 points on 3-of-4 shooting, made all four of his free throws, grabbed three rebounds, blocked one shot and drew a charge.

The Celtics stretched their lead to as many as 13 points in the third quarter. A late Mavericks run cut it to six, but Payton Pritchard closed out the frame with a buzzer-beating 34-footer to shift momentum back in Boston’s favor.

Pritchard added a steal minutes into the fourth to set up a fast-break Brown dunk, and Tatum drilled his first three of the night on the Celtics’ next possession to push their lead back to double digits.

Porzingis’ status will be worth monitoring as the series shifts to Dallas. The 7-footer came up limping during the second half and was seen receiving treatment on the Celtics bench. He played 23 minutes and finished with 12 points.