Cleveland’s Jarrett Allen competes for a rebound with Boston’s Al Horford, left, and Jayson Tatum in the first half of Wednesday night’s game at Cleveland. Ron Schwane/Associated Press

CLEVELAND — Darius Garland scored 29 points in his return after missing five games with an ugly eye injury, Donovan Mitchell added 25 and the Cleveland Cavaliers beat the Boston Celtics 114-113 in overtime on Wednesday night for their sixth straight victory.

Garland added 12 assists, including an alley-oop to Mitchell in OT that put the Cavs up 112-109 in their second victory over the Celtics in less than a week.

Jayson Tatum’s basket with 1:04 left pulled Boston within a point, and thanks to some poor possessions by Cleveland, the Celtics had a chance to win it at the buzzer before Jaylen Brown’s 18-footer went off the back of the rim.

Brown scored 30 and Tatum 26 for the Celtics, who were looking to avenge an OT loss at home last week to the Cavs, who overcame a 15-point deficit.

Tatum forced this overtime with two sensational plays in the final 6.7 seconds.

First, he drove the lane for an emphatic dunk — and may have been fouled by Jarrett Allen — to tie it 107-all. Then, on Cleveland’s final trip of regulation, he blocked Mitchell’s step-back 3-pointer as the horn sounded.

Garland had been out since the season opener on Oct. 19, when he was accidentally swiped across the eye by Toronto’s Gary Trent Jr. A nasty cut under his eyelid and excessive swelling kept Garland on the bench in sunglasses.

But back doing what he does best, the 22-year-old Garland led the Cavs to another signature win in this young season. Cleveland rallied to beat the defending Eastern Conference champions in overtime on Friday.

Allen added 14 points and 14 rebounds for the Cavs, who had some offensive issues while welcoming Garland back.

Garland didn’t show a speck of rust early on, making his first three 3-pointers and scoring 14 points in the first quarter — his career high for the first 12 minutes. He added three assists, two steals and moved around the floor with his usual fluidity.

NOTES: Brown and Tatum each have six 20-point-plus games. …. G Derrick White has taken four charges. G Marcus Smart, the only other Boston player to do so, has taken two. … C Robert Williams (left knee surgery) have been inactive for every game, but could return before the end of December.