BOSTON — It’s been more than an hour since the Celtics concluded their off-day workout and Jaylen Brown has finally elected to clock out.

He hadn’t planned to stay this long but sometimes these things happen. Brown had been doing some post-practice shooting drills this week with teammate Terry Rozier and that eventually spawned a free-throw shooting contest that Brown, a career 65.8% charity-stripe shooter, is proud to say he won.

Brown had started making his way off the court in the aftermath. But to do so he had to cross in front of late-season signee Jonathan Gibson, who was shooting deep 3-pointers alone. Brown decided Gibson needed a defender and that led to another competition, this time a modified 1-on-1 game highlighted by Brown volleyball spiking a tipped Gibson shot attempt so violently that the ball rolled to the other side of the two-court gymnasium as Brown screamed to the amusement of the few stragglers nearby.

After fetching the ball, the game resumed. Eventually, the only people left near the court were Brown, two media relations staffers who patiently agreed to wait for a couple of reporters to finish up interviews, and some assistant coaches who seemed eager for everyone else to clear out so they could engage in their own afternoon hoops game.

"Sorry to keep you waiting,” Brown said to the last remaining reporter, which, in this "Next Question" era seems particularly notable. As it turns out, it’s also a good way to tell the story of Brown’s 2018-19 season.

Sorry to keep you waiting.

Brown acknowledges now, while reflecting on a season of highs and lows, that he failed to live up to his own lofty expectations at the start of the year. He said he had to get himself off social media for long stretches early in the year to avoid the eggs filling his Twitter mentions with acid-tongue critiques or suggestions that he ought to be traded. Brown didn’t let the negativity affect him but he was also his own harshest critic.

"Somebody has to take the blame, somebody has to be the scapegoat. Early in the season, I guess I was a part of that, or one of those scapegoats,” said Brown. “But I didn’t really look at it as a negative thing, I looked at it as, ‘OK, I’m going to play better, so nobody can say anything.’”

His critics are a lot quieter now, particularly after a fantastic first-round series in which Brown, elevated to a start in place of the injured Marcus Smart, gave the Celtics a little bit of everything in a four-game sweep of the Indiana Pacers. Brown brought Smart-like defensive intensity in Game 1, made a key late-game feed to Jayson Tatum for the winner in Game 2, and provided a much-needed scoring punch in Game 3.

By Game 4, he was so hyped about the team’s impending sweep that he repeatedly got caught making broom motions in front of the Boston bench late in the fourth quarter.

"I didn’t mean that in any sort of disrespect to Indiana. I didn’t mean that to be an arrogant gesture,” said Brown. "I’ve never swept a team in the playoffs, so that was my first time. And it was just an overwhelming type of feeling.”

It’s at this point that we told Brown that the only flak he caught on social media for the broom pantomiming was his unorthodox sweeping technique.

"I can’t remember the last time I actually used a broom,” said Brown ."Maybe the next time we sweep, I’ll be better.”

Brown isn’t thinking about brooms now, not with the challenge in front of him: Slow down a Bucks team that was the NBA’s best over the course of an 82-game regular season, all while trying to bottle up potential league MVP Giannis Antetokounmpo.

In typical Brown fashion, he yearns to meet the challenge head-on. Back in December, Brown dunked on Antetokounmpo late in a frustrating loss to the Bucks in Boston. He stared down the Greek Freak in the aftermath of a thunderous left-handed jam and earned a tech for taunting.

Brown raised some eyebrows this week when asked if he considered Antetokounmpo the MVP of the league and offered a “No comment” response. Truth be told, he’s quite a fan of Antetokounmpo’s game.

"Giannis is a great player. He’s probably one of my favorite players in this league, just based off his mentality and his aggression alone,” said Brown. "I love aggressive players. I consider myself an aggressive player but people like Giannis [and] people like me are not easily intimidated. Actually, it amps us up going against somebody like Giannis.

"It’s probably going to bring the best out of me in terms of my aggression, in terms of physicality because, against him, if you’re not locked in, if you’re not aggressive, if you’re any form of weakness, he’s going to expose you. Like, he seeks that out. I’m not going to show him and I’m not going to give him anything to feed off of. I’m looking forward to it.”

Brown could be vital to Boston’s success in Round 2, particularly if Smart is again out the entire series. But Brown can’t quibble with opportunity. After all, that’s what he so desperately yearned for amid the rocky start to the year.

"To me, [the start of the year] was tough in the sense that, you had high expectations with not the same role. For me, that was the challenging part,” said Brown. "Not what people were saying, not what the media was saying. I didn’t care. It was me, the pressure I put on myself was the biggest part, more than anything. Because I wanted to do more but I didn’t have more in front of me. So, that was the hardest part, like criticizing myself. I’m my biggest critic.”

Well, sometimes his teammates are his biggest critics. They, along with Boston coaches, are not bashful about pointing out Brown’s miscues when they happen. Late in Game 4 against the Pacers, cameras caught Kyrie Irving having a firm conversation with Brown coming in and out of a late-game timeout. Teammates admit they push Brown because they know what he’s capable of.

But, this reporter wondered, does Brown feel like teammates yell at him a lot?

"Do I think my teammates yell at me a lot?” Brown said, repeating the question. "To be honest, I’m not even sure how to answer that question.”

We explained how it simply seemed like Brown was more likely than others to get told what he did wrong on a play.

"For sure,” Brown relented with a smile, to which we noted that was probably just human nature to feel that way.

"It is. But I don’t even pay attention to it. I have a job to do and I try to do it to the best of my ability,” said Brown. "As a player, you learn to handle situations better as you get older. And I’ve learned so much this year. Just about myself as a person, myself as a basketball player. I still have a lot to learn and I realize that.

"Sometimes I can be willing to learn more, even though I am willing to learn, sometimes the best thing to do is just be quiet. I’ve learned that as well. I just gotta continue to keep learning. I’ve learned a lot in this league, and I’ve accomplished some stuff in this league. And I want to accomplish more. I gotta keep listening and, at times, I can be more open to that.”

It’s all part of the maturation process. He’s eager to grow and blossom but sometimes it simply takes time.

And one thing is clear: Jaylen Brown doesn't mean to keep you waiting.

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