Donovan Mitchell and the Cavaliers get revenge on the inferior Celtics

CLEVELAND – The Celtics were so close to getting their most rewarding win of the season considering they were missing two starters.

But the defensive slump began at a critical time, with Donovan Mitchell leading the way down the stretch and Jayson Tatum unable to match his performance. After leading by 12 points with 8 minutes left, the Celtics allowed Mitchell to single-handedly bring his team back with four 3-pointers, and Boston was helpless in a 115-111 loss.

Mitchell scored 20 of his 35 points in the fourth quarter as the Celtics’ shifting defense constantly left him open at the left elbow for three-pointers.

Tatum scored 33 points for Boston, but only 4 in the fourth quarter, and he missed two crucial shots down the stretch that would have stopped Cleveland’s run.

Evan Mobley’s streaking layup completed a 24-8 run and gave the Cavaliers a four-point lead with 34 seconds left. Payton Pritchard scored 24 points for the Celtics and Kristaps Porzingis added 21 points and 8 rebounds.

Given the circumstances, the Celtics played one of their better quarters of the season and pulled away in the third quarter. Behind Tatum’s 19 points and a stifling defense, the Celtics led by as many as 14 points late in the quarter after a jumper by Tatum.

The Cavaliers made 3-pointers in the early going but couldn’t get a clean shot against the Celtics’ shifting defense, especially given the presence of Kristaps Porzingis, who assumed his role as a rim protector. Sam Hauser, who played significant minutes, made three 3-pointers in a 2:04 span of the third period.

Boston made 7 of 13 3-pointers and 54 percent of its shots to build an 84-72 lead heading into the fourth period. Tatum scored 29 points in three quarters, while Porzingis contributed 17 points and Hauser scored 13 points. Two-way swingman Drew Peterson added eight points in 18 minutes, while Celtics coach Joe Mazzulla reached deep on his bench with Derrick White (foot) and Jaylen Brown (not) to produce. Due to the injury, Mazzulla had to play with the He was creative in his starting lineup and rotations, and he gave Hauser his first start of the season and gave Peterson significant minutes.

In his seventh NBA appearance, Peterson played the entire second period, scoring 5 points with 3 rebounds as the Celtics briefly took the lead with an 18-6 run. After the Cavaliers scored 7 straight points, Jrue Holiday and Peterson combined for the final 4 points and Boston only trailed 51-49 at halftime.

Cleveland entered this game healthier than it was in Boston two weeks ago, with Isaac Okoro and Caris LeVert healthy, and also got 11 first-half points, including three 3-pointers, from Lawrence native Georges Niang. The Cavaliers led by as many as 11 points, but the Celtics continued to fight back with strong interior defense and 12 points from Porzingis.

The Celtics stayed close despite making just 8 of 27 3-point attempts in the first half, including a combined 2 for 12 from Tatum, Pritchard and Holiday. Cleveland cooled off after a hot first quarter as Mitchell and Mobley combined to shoot 3-for-16.

The mood for Sunday’s game has been dampened in recent days after Cleveland lost twice in three days to the Atlanta Hawks, including an NBA Cup loss on Friday that gave the Hawks the Group C title. The Cavaliers started the season 15-0 before losing to the Celtics on November 19th at TD Garden.

Cleveland entered having lost three of five games, and Mitchell made a combined 15 of 47 shots in those two losses in Atlanta. The Celtics countered the Cavaliers’ size by using Porzingis and Al Horford in the starting lineup, even though the club had another game against the Heat on Monday.

Gary Washburn is a Globe columnist. He can be reached at [email protected]. Follow him @GwashburnGlobe.