DALLAS >> Jayson Tatum poured in 31 points and Jaylen Brown supplied 30 as the Boston Celtics held off a late rally by the Dallas Mavericks for a 106-99 victory tonight in Game 3 of the NBA Finals.

By taking a commanding 3-0 lead in the series, Boston pulled within one victory of its 18th title in franchise history. The Celtics will have a chance to complete the sweep on Friday when they collide with the Mavericks in Dallas for Game 4.

Tatum bounced back today after combining for just 34 points in Games 1 and 2. Brown added eight rebounds and eight assists for Boston, which also got 16 points from Derrick White. Big man Kristaps Porzingis (lower leg) didn’t play after getting injured in the third quarter of Game 2.

Like Tatum, Kyrie Irving made up for a lackluster showing in each of the first two games of the series, and he paced the Mavericks with a game-high 35 points. Luka Doncic went for 27 points, six boards and six assists, but he dealt a critical blow to Dallas’ comeback hopes by fouling out with 4:12 left in the game.

The Mavericks challenged the foul on Doncic, but the call stood, forcing him from the game.

It looked like the game was over when White drilled a 3-pointer with 11:07 left in the fourth quarter to put the Celtics up 91-70.

But Dallas then took over, rattling off 28 of the next 37 points to get within 100-98 following a Dereck Lively II dunk with 1:20 to go.

Brown made sure Boston never let the Mavericks draw even, though, and his mid-range jumper at the top of the key made it a four-point game with 1:01 remaining. P.J. Washington and Irving both missed 3-point attempts down the stretch before two free throws from White and two more from Tatum put the finishing touches on the victory.

Doncic’s layup had the Mavericks within six, 71-65, with 5:11 left in the third quarter. The Celtics answered with a 7-0 spurt and later took an 85-70 lead into the fourth.

After Dallas led by as many as 13 in the opening 12 minutes, neither team led by more than four in the second quarter. The first half ended with the Mavericks clinging to a 51-50 edge behind 20 points from Irving.

Boston outshot Dallas 46.3 percent to 44.2 percent for the game.