At the Celtics’ absolute best — which everyone knows can win a championship — this is the Derrick White they need stepping up in the biggest moments. The now-familiar sight of White confidently rising up for a 3-pointer is etched into the minds of fans who watched the C’s win it all last season.

It’s no coincidence that White’s struggles coincided with a down couple months for the Celtics. It’s not all on White, of course, but the C’s need him as a guy they can consistently rely on. And in a marquee East showdown against the Cavaliers on Tuesday, White delivered. The guard scored 14 of his 20 points in the fourth quarter, knocking down big-time shots in the process. His recent slump appears to be in the rear-view mirror as he helped lead the Celtics to the win over the Cavs.

“I’m just trying to make shots,” White told reporters in Cleveland. “Especially in those moments, JB, JT, KP get a lot of attention and they’ve got to live with something. So just try to step up and shoot it with confidence and knock them down, and I was able to do that tonight.”

As White pointed out, the Celtics employ guys who suck up the oxygen on the offensive end. Teams aren’t going to just let Jayson Tatum beat them, often doubling him to get the ball out of his hands. That’s where White can feast off open looks as another matchup problem on the perimeter.

White poured in 20 points, five rebounds, two assists, two steals and a block in his 35 minutes Tuesday. A little bit of everything — that’s his game. It wasn’t a perfect night as he beat himself up a little over his two missed free throws. But all that matters is the Celtics walking away with the 112-105 win over the first-place Cavaliers in their house.

“He’s one of the most clutch players on our team honestly,” Kristaps Porzingis said. “I feel like he always hits big shots. Not tonight, but usually he has some deep corner ones. He’s a rhythm player and once he gets in that kind of rhythm and starts hitting those pocket 3s and making plays, he’s very, very special.”

White finished 6-for-12 on 3-pointers Tuesday, upping his percentages over the last five games. He’s now shooting 22-for-47 (46.8%) from 3 over that stretch, heating up after a cold-shooting January.

Just in time, too, as the Celtics are finally starting to string wins together again. When they played mediocre basketball in December and January, streaks were a rarity as they often flip-flopped wins and losses. But they finished their road trip a perfect 3-0 with some renewed confidence in their guys. They now have a chance to finish these final four games before the All-Star break strong before getting in some rest.

“It was big, we needed that from him,” Tatum said. “He really got it going in the fourth, just being aggressive. He’s an integral part of our team. When he’s hitting shots and being aggressive, we’re just that much harder to guard.”

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