Cleveland’s Evan Mobley is fouled by Boston’s Mike Muscala in the first half Monday night in Cleveland. Ron Schwane/Associated Press

CLEVELAND — Donovan Mitchell scored 40 points and Lamar Stevens fueled Cleveland’s fourth-quarter comeback with his hustle, leading the Cavaliers to a 118-114 win on Monday night over the Boston Celtics, who lost their second overtime game in less than 24 hours.

Evan Mobley added 25 points and 16 rebounds for the Cavs, who improved to 7-0 in OT while avenging a loss in Boston five days ago.

Jaylen Brown scored 32 points and Malcolm Brogdon 24 for the Celtics, who didn’t arrive at their hotel in Cleveland until 2:30 a.m. after losing to the New York Knicks in double overtime on Sunday.

The Celtics, who were without All-Star Game MVP Jayson Tatum, blew a 14-point lead in the fourth and had a chance to win it in regulation. But Grant Williams missed two free throws with 0.8 seconds left and Boston’s Marcus Smart barely missed a tip-in at the horn.

The frenetic final seconds of regulation included a pair of debatable fouls that led to replay challenges from both teams.

With Stevens doing the dirty work underneath, the Cavs battled back and tied it on Mitchell’s two free throws with 5.8 seconds left. Boston’s Derrick White dropped a 3-pointer with 14.3 seconds remaining.

After playing just nine seconds in the first three quarters, Stevens came off the bench and grabbed eight rebounds and scored eight points, including a 3-pointer with 2:14 left in OT to put Cleveland ahead 114-112.

Stevens scored again before Brown’s layup with 43 seconds left pulled the Celtics within 116-114.

However, Darius Garland made a pair of free throws with 9 seconds to go for the Cavs and after securing the final rebound, Mitchell slammed the ball off the floor as Rocket Mortgage FieldHouse erupted following a win that was probably tougher than needed.

NOTES: Brown added 13 rebounds and 9 rebounds, just missing his first triple-double this season. … C Al Horford also stayed back in Boston to rest a sore back. … Boston dropped to 1-3 vs. Cleveland. … Coach Joe Mazzulla didn’t provide specifics on Tatum’s injury, but said he doesn’t expect it to sideline him for long. … C Robert Williams is expected to miss up to 10 days with a hamstring strain. … Smart celebrated his 29th birthday and Mazzulla credited the team’s “emotional leader” with a “beautiful ability to control the game.”