Celtics center Tristan Thompson defends against Indiana’s Doug McDermott during Boston’s 118-112 win Friday night in Boston. Elise Amendola/Associated Press

BOSTON — The Boston Celtics have been searching for a spark to pull them out of one of their worst stretches of the season.

Kemba Walker answered the call with his best game of the season.

Walker made two late free throws and scored a season-high 32 points to help the Celtics snap a three-game losing streak with a 118-112 win over the Indiana Pacers on Friday night.

Daniel Theis added 17 points and Jaylen Brown finished with 15.

“It felt good,” Walker said. “We played hard. We had a slow start, but we stayed together. That was the best part about it.”

Indiana open an 18-4 but never led in the final 24 minutes in losing for the third time in four games.

Domantas Sabonis led the Pacers with 24 points and nine assists. Justin Holiday added 19 points and five rebounds.

A 12-4 run by the Celtics, capped by a driving layup by Walker, gave Boston a 110-101 cushion.

Indiana pulled within 112-109 on a layup by Sabonis with 1:23 to play. A turnover by Brown then gave the ball back to Indiana.

Holiday missed a 3-pointer from the corner and Theis hit one on the other end. On Indiana’s next possession, Sabonis got a friendly bounce off the top of the backboard on a deep 3 that trimmed Boston’s lead to 115-112.

The Celtics nearly got an 8-second violation, but Walker hustled the ball up the court and was fouled, and connected on his two ensuing free throws with 11.6 seconds remaining to help seal it.

The Pacers started fast, scoring the game’s first 12 points, which included a pair of 3-pointers and a three-point play by Myles Turner. But Boston closed the quarter on a 28-13 run to take a 32-31 lead.

Tatum and Brown combined to shoot just 2 for 8 from the field for seven points in the opening quarter.

Most of the heavy lifting for the Celtics’ comeback came from other sources. Their bench stepped up, contributing 27 points in the first half to help Boston take a 61-60 lead into the break.

Boston’s reserves held a 39-34 edge in bench scoring, led by Robert Williams and Jeff Teague, who had 14 points each.

“We believe,” Teague said. “We just gotta continue to keep working. I think the locker room is even getting even closer. It’s pretty amazing how the losses bring you closer than the wins do.”