The Celtics trailed by 19 at halftime. Boos from the TD Garden crowd trailed them as they headed to the locker room. Inside, Joe Mazzulla and Derrick White shared a light moment.

“I just laughed with him,” Mazzulla said. “We both agreed it was probably the worst half he’s ever played in his career.”

He probably wasn’t far off. At least by the standard White has set for himself. The do-it-all guard had hardly made an impact on the game. He had as many turnovers (2) as points. He missed four of his five shots, including when he completely gaffed on a layup attempt and hit nothing but air.

On one sequence in the second quarter, White committed a turnover and then slipped and fell running back on defense, allowing the Pistons to get another easy basket.

White needed a change. So, after a few slips in the first half, he switched out his shoes from an orange pair to some blue ones.

“It was like, I might as well try something else,” White said. “That was a horrible first half, so I just had to try something else and start playing a little bit better.”

As for his conversation with Mazzulla?

“He didn’t even have to tell me. I knew that. Anything that could go wrong was going wrong for me there. It was just a rough first half. Just took those 15 minutes to reset again and get back after it.”

It had to be the shoes. White looked like a different player in the second half, or at least the one the Celtics expect on a nightly basis. He scored 21 points in the second half and overtime, including 10 in the extra session, as he helped spur the Celtics’ thrilling comeback win over the Pistons. He was everywhere. He recorded two blocks in the fourth, including another terrific swat in transition. His deep 3-pointer late in overtime helped seal the game.

White does not have bad stretches often. He’s been arguably the Celtics’ most reliable and consistent player this season, which has given him some buzz for All-Star consideration. It wasn’t stunning how he responded in the second half, but it further solidified how much he can be counted on.

“He just kept playing,” Mazzulla said. “Kind of laughed about it and didn’t change anything, and he went out and played a great second half. So guys like him, he has great poise, great stability. That’s probably the first time I’ve ever seen it just not go his way. And I really liked how he responded.”