BOSTON – Celtics forward Jaylen Brown struggled with back-to-back technical fouls on coach Joe Mazzulla and himself late in the fourth quarter as Boston lost 117-108 to the Chicago Bulls on Thursday night.

Boston led 86-82 before Chicago opened the final period with a 17-4 run to take a 99-90 lead.

The Celtics scored six straight points before Mazzulla and Brown were called on consecutively against the Techs with 5:12 to play after both protested a non-foul call as Brown fought for a loose ball. Instead, a jump ball was called.

Brown said he reached out to referee Justin Van Duyne for an explanation about Mazzula’s technique, which Brown felt was unwarranted. Brown was also ultimately whistled for a technical error.

“I said to (Van Duyne), ‘You called a technician for no reason.’ He said, “If you tell me again, I’ll call another technician,” Brown said. “You can’t threaten the boys with a technical foul, that’s not part of the game. If you want to punish guys for gesticulating and all that stuff – then that’s good. That’s nonsense—-.”

Mazzulla said Van Duyne told him his technique was to walk down the field after the jump ball call. This was confirmed by a Pool Report interview with crew chief Tony Brothers, who said Mazzulla’s technician was responsible for leaving the trainer’s box and getting on the ground.

“The referee had to do his job when I was on the pitch and that was it,” Mazzulla said.

Brothers said Brown’s technique was because “he questioned our integrity multiple times during the same sequence.”

LaVine hit both free throws that followed and then hit a 31-footer to put Chicago back in the lead, 104-96. Later in the period, Tatum also caught a technical that helped extend the Bulls’ lead to 10.

Mazzulla remained agitated at the end of the game and tried to get close to Van Duyne by yelling in his direction. Mazzulla was held down by two assistant coaches.

Asked what he said to Van Duyne after the game, Mazzulla shrugged.

“I just hadn’t seen her in a while, just Merry Christmas, Happy Holidays,” he said.