BOSTON — The Boston Celtics’ disastrous 2018-19 season came to an end on a Wednesday in May. The dejected squad dressed quietly in a Milwaukee locker room, then flew back to Boston the next morning. A few players talked to the media, but they didn’t have any answers. Nobody really did.

The next morning, Celtics assistant coach Tony Dobbins got a text: Could he get to the practice facility? Jaylen Brown wanted to get in the gym.

Dobbins was a little incredulous at first. Immediately after the season, players are encouraged to let their bodies heal from the day-to-day grind of an 82-game-plus-playoffs season.

“We just finished the other day,” Dobbins told Brown. “You sure you don’t want to take a step away, take some time?”

Brown’s answer: “Nah. Let’s get it. Let’s get after it.”

One thing was clear: After enduring one of the strangest seasons in recent NBA memory, Brown didn’t want to waste time.

Early success

In previous summers, Brown traveled frequently back to Atlanta for workouts. As a 12-year-old, he began his career working with Atlanta-based trainer Desmond Eastmond after Brown’s uncle Steve Bouye — father of Jacksonville Jaguars cornerback A.J. Bouye — introduced him to Brown’s mother. Eastmond recognized Brown’s talent, and they started training together full time during Brown’s freshman season in high school.

Brown’s workouts with Eastmond were intense as well, of course. Eastmond worked with Brown on shooting and ball-handling, incorporating aquatics and boxing. They also watch film together, and while Eastmond trains Brown as a 3-point shooter and slasher, he wishes Brown had more opportunities to get to his mid-range game. Brown is hitting 45 percent from mid-range, according to Cleaning the Glass, which is 74th percentile at Brown’s position.

“His mid-range game is really beautiful,” Eastmond said. “I would love to see him go to that more.”

Brown spent some time in Atlanta this summer, and he played for Eastmond’s Summer League team. But unlike previous seasons, Brown had business in Boston.

“I wanted the front office, I wanted the people on the coaching staff to see my face,” Brown said. “See, I’m in here; see, I’m getting better so it’s easier when you’re building an offense, building a team, it’s easier to have me a part of it because I’m here all the time.”

Becoming a leader

Brown signed a four-year extension worth up to $115 million this offseason. Some around the league wondered about the wisdom of handing that much money to a player who appeared to stagnate in his third year.

The Celtics didn’t need to worry. Brown has put together an incredibly promising start — 19.9 points and 6.9 rebounds per game in 17 contests while shooting 49.4 percent from the field and 38.2 from three. Even his free throw shooting is up to 71.8 percent from 65.8 percent last year. In five of his last six games, Brown has posted 22 points or more.

One of the more underrated aspects of Brown’s game is how he fits into a team’s concept. Two years ago, the Celtics needed him to step up in the playoffs with Irving and Gordon Hayward sidelined. Brown averaged 18.5 points per game and helped lead a charge to the Eastern Conference Finals that nearly produced a trip to the Finals.

Last year, the Celtics needed Brown to be an energy guy off the bench, and he was one of the few players on the Celtics’ roster who could reasonably look back at the Milwaukee series without cringing at his own performance.

“He’s just going to do what the coaches ask of him,” Eastmond said. “But because he knows that ‘Boston is my home now,’ I think he’s going to just let it loose.”

Brown refused to classify last year as “frustrating.” After all, he’s a chess player. Everything is a learning experience.

“I’ve never been one to complain, complain, complain,” Brown said. “I try to take it for what it is, make the best of the situation, then the next year when I do get the opportunity I wanted, I don’t leave no room for doubt.”