BOSTON (CBSDFW.COM/AP) — Kemba Walker took on some extra responsibility at the offensive end in Boston’s first game since Gordon Hayward broke his left hand.

Walker made a trio of key 3-pointers in the fourth quarter and finished with 29 points, Jaylen Brown added 25 points and 11 rebounds, and the Celtics beat the Dallas Mavericks 116-106 Monday night.

“I was just trying to be aggressive, trying to make the right plays,” Walker said. “My shot felt good the whole night. I was just missing them. Then, in the fourth quarter, just naturally, the competitive nature just comes out and I try to do what I can do to put the ball in the basket.”

Marcus Smart scored 17 points, Daniel Theis chipped in with 11 and Brad Wanamaker had 10 for Boston, which won its eighth straight game since a season-opening loss at Philadelphia.

Jayson Tatum shot 1 for 18 from the field and scored only five points for the Celtics.

Luka Doncic led the Mavericks with 34 points, nine assists and six rebounds. Maxi Kleber had 15 points with eight boards.

Kristaps Porzingis scored just four points on 1-of-11 shooting for Dallas.

“Porzingis had a tough night. We’re just going to flush it and move on,” Mavericks coach Rick Carlisle said with a laugh. “You know, there’s nights like this. You’ve just got to flush it and move forward.”

Porzingis took a lot of blame for the loss.

“I had an off night tonight, and guys stepped up,” he said. “Guys fought until the end, and we were right there. If I had a better game, the result could have been much different.”

The Celtics released a statement during the opening quarter that said Hayward had surgery Monday to repair a fracture in his non-shooting hand. He was injured during their previous game in San Antonio when he collided with LaMarcus Aldridge as the Spurs’ big man set a screen.

“I got word at halftime that surgery went well,” Boston coach Brad Stevens said. “We’re going to have to find other guys to step up, especially off the bench.”

Boston trailed by two before going on an 11-2 spurt over a 1:32 stretch to move ahead 101-94 with 4:11 to play on Walker’s 3 from the right wing. Smart then converted a three-point play.

Walker nailed his three big shots from beyond the arc in a span of 1:09.

Dallas took its first lead, 88-86, on Tim Hardaway Jr.’s one-handed runner in the lane. The Mavericks held a 92-90 edge before Walker took over.

The teams were tied at halftime before Boston opened the second half with a 15-3 surge. Smart started the run with a 3 from the right corner. Walker and Brown added 3s on consecutive possessions.

Doncic then started to take over, scoring nine of the Mavericks’ 11 points as they closed to 84-79 at the end of the third quarter.

The Mavericks are now 6-4 on the season and will look to get revenge at the New York Knicks Thursday evening.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)