BOSTON (CBS) — Last year, a wrist injury ended Jaylen Brown’s season just before the playoffs. It led to some disappointing results for the Celtics, and has Brown extremely amped up ahead of Boston’s first-round rematch with the Brooklyn Nets.

Maybe a little too amped up, at least for now. He says he won’t be when the series finally tips off Sunday afternoon at TD Garden.

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“I’ve had a little bit of trouble sleeping, so I’m trying to calm myself down. It’s playoff time, the best time of the year and the time of the year that you work for,” Brown said Thursday. “Just going out and breathing, being yourself is going to be key. I know there is going to be a lot of energy in the Garden, so sometimes the more calm and relaxed a player is, they’re the one who gets the advantage.

“I’m trying to stay balanced, but I’m definitely excited,” said the 25-year-old. “You can tell by the smile on my face, right?”

He had a smile on his face Thursday, but Brown is all business come game time. And he knows the business ahead isn’t going to be easy. Not with Kevin Durant and Kyrie Irving on the other side.

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Boston took three of four against Brooklyn during the regular season, but Irving and Durant were together for only one of those. Durant went off for 37 points while Irving had 19, but the Celtics escaped with a six-point victory in Boston. It was not an easy win by any stretch, and Brown expects some pretty hard-fought games in the future.

But it’s a challenge that Brown and the Celtics are more than ready for.

“What more can you ask for? Those are two of the best offensive players to touch the ball in NBA history,” he said of Durant and Irving. “Those are two offensive juggernauts. What they do with the ball is special. It’s going to take everybody to win.”

But that has been the backbone of the Celtics’ incredible second-half turnaround; everyone doing their job and playing their role. Brown applauding this squad’s inner strength, which he likened to the 2018 Celtics, who went on a surprising run to the Eastern Conference Finals without an injured Irving, led by Brown and Tatum, who was a rookie.

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“There is no giving up; that isn’t even in the vocabulary. There is no backing down,” Brown said of the 2021-22 Celtics. “We embrace and accept all challenges. That’s how we turned things around. We have a bunch of tough guys with great inner strength about them in the locker room, and that carries over to the court.”