He eventually agrees to open the curtain on a class with his Brazilian professor, Alex Costa, a tank of a man who looks like he could crumple a full beer can with two fingers. There are conditions, however.

The regular season has just ended, and Mazzulla will cooperate only if the story is published after the Celtics win a playoff series. He wants the location of his sparring session to remain private. He says I cannot record it or tell anyone that I’m there. He is not smiling when he sets these boundaries.

And that is how we recently ended up in a cramped, windowless room that can’t be described in much more detail, with Mazzulla changing out of Celtics workout gear and into a gi, a uniform consisting of loose pants and a robe-like long-sleeved top, held together by a belt.

“I can only let people know what Joe allows me to,” Costa says, “so there’s a lot of secrets involved.”

Mazzulla places his crucifix necklace, smartwatch, and iPhone on a small table, along with two bottles of electrolyte-infused water. Then he and Costa drag in three large red mats that Costa has brought from his Commonwealth Avenue gym. They tape them together into a makeshift ring. It’s intense.

“We need the best of you, and we’re going to do it,” Costa forcefully tells Mazzulla. “We’re on the way.”

In about 90 minutes, Mazzulla will be lying on the mat, covered in sweat, gasping for air, telling Costa he is finished, even as Costa tells him he is not. This is the feeling Mazzulla believes will help him during the most unforgiving, stressful moments of these playoffs. This is the feeling he has needed.

The right sensei

Mazzulla has had a passion for martial arts since his father, Dan, signed him up for karate lessons as a child. He began taking jiu-jitsu classes when he became head basketball coach at Division 2 Fairmont State in 2017 but stopped when he was hired as a Celtics assistant two years later.

When he became Boston’s head coach following Ime Udoka’s suspension last fall, he needed to fill a void.

“It was important to have something where I was being coached every day, where I was being challenged, so I could use that to help my leadership,” Mazzulla said. “I thought it was very important to get back into it as fast as I could.”

Celtics director of team operations Kara Keena conducted an exhaustive search for a sensei. She combed through local instructors and sought references, eventually landing on Costa, 47, a Sao Paulo native who helps run the Gracie Barra gym that sits in the shadows of Boston University.

Mazzulla and Alex Costa: student and teacher. Craig F. Walker/Globe Staff

When Costa’s chronic asthma and bronchitis kept him from playing soccer as a child, he began training in martial arts to learn to control his breathing. He practiced judo, Muay Thai, and boxing, but jiu-jitsu became his love.

He won five International Brazilian Jiu-Jitsu Federation world titles before his career was derailed by knee injuries about 20 years ago. Uncertain about his next step, he moved in with his brother in Boston, found temporary work in the food service and construction industries, and studied to improve his English while teaching jiu-jitsu on the side.

But his client list grew quickly, and in 2010, he and his wife, Ashley, helped open the Boston gym. The couple and their three daughters relocated to Denver a few years ago for family reasons, and Costa also ran a jiu-jitsu school there while overseeing the Boston facility from afar.

“I thought it was a prank when the Celtics called,” he said. “But I found it a chance to be the biggest challenge of my career, to help someone using jiu-jitsu to apply it to being a basketball coach.”

Unbeknownst to Mazzulla, Costa spent five months commuting from Denver to work with his eager, high-profile client. Costa crashed on friends’ couches, in motels, or even in his gym. When Mazzulla eventually learned of the unusual arrangement, he invited Costa to stay with him, but Costa declined because he did not want to disrupt Mazzulla’s family environment.

Mazzulla has learned to bring the lessons of the mat to the hardwood.Craig F. Walker/Globe Staff

Costa has joined Mazzulla on several Celtics road trips and attends each home game. He also studies Mazzulla’s press conferences, looking for any indicators of how the coach might need him most.

Although their sessions are fights, Mazzulla views them as puzzles. The quick, precise decisions required on the mat have helped him make calculations while 20,000 people watch him work.

“The mat brings an awareness, a humility, and a level of discomfort and being challenged that really benefits me,” Mazzulla said. “You have to go to places to lose in order to win. Because of my inexperience, it’s where I go to lose.”

Mental and physical challenge

Mazzulla is warming up in the makeshift gym as he and Costa talk about the newest challenge facing the Celtics, who are preparing for their first-round playoff series against the Hawks. The Celtics won all three regular-season games against Atlanta, and that concerns Costa.

“The team who lost three times will come in with more desire,” he says. “You will more naturally relax because you’ve gotten the job done. But the ones who got the punishment you gave, it never goes away.”

Mazzulla insists he is here for the mental challenges jiu-jitsu presents. But it is clear he also relishes physical competition. He has yet to defeat Costa, and that frustrates him.

Costa, who is a few inches shorter but heavier and stronger than Mazzulla, emphasizes that he has trained in jiu-jitsu for most of his life. He should dominate.

“It’s OK to get mad,” Costa says. “No problem with that. Madness does exist for a reason. Just don’t let your mind-set drop.”

“The mat brings an awareness, a humility, and a level of discomfort and being challenged that really benefits me,” Mazzulla said.Craig F. Walker/Globe Staff

Costa’s English is quite good, but he is aware of imperfections. Sometimes he’ll stop in the middle of a movement and ask Mazzulla how to say a word. Most often, he just follows up instructions with, “Does that make sense to you?”

Mazzulla nods to show that it does.

Today, they start with individual exercises. Mazzulla lies down before jumping to his feet without using his hands. He pulls Costa toward him with his legs. He does some side rolls. He is breathing harder after completing 10 repetitions of each maneuver.

“It feels more natural,” he tells Costa. “It feels different.”

During a grappling drill, Costa turns and hurts his arm. He blames himself for the misstep.

“God damn it!” he yells.

Mazzulla, a devout Christian, freezes.

“Don’t swear,” he says.

Costa is confused.

“I thought ‘damn,’ it is not a swear?”

So the session stops for a brief discussion about the variations of English cursing. Mazzulla explains that using the Lord’s name in vain is different.

“ ‘Damn’ is OK,” he says. “ ‘God damn it’ is a swear.”

Costa squints and nods.

“OK, thank you for letting me know,” he says. “I won’t say that now.”

Moments later, they’re back at it, with Mazzulla wrapping Costa in a submission hold. Costa taps Mazzulla’s arm, the universal signal to let go. But for a man struggling to breathe, Costa is ecstatic.

“That was very good,” Costa says. “I mean, horrible for me to take, but very good technique.”

Breathing, while essential to maintain consciousness, is also important to maintain composure and focus. At the start of the NBA season, Mazzulla’s relentless gum chewing during games became a source of humor for Celtics fans, but after working with Costa, he realized it was disrupting his breathing. He hasn’t chewed gum since.

‘One more round!’

During classes, Costa refocuses on the big picture with subtle nods to the NBA. When there is one rep left in an exercise, he calls it Game 7. He tells Mazzulla that during a match it can be hard to maintain the initial plan of attack, because circumstances change suddenly, just like in basketball. Fighters and coaches have to adjust.

Now, they begin an advanced move in which Mazzulla grapples with Costa before essentially swinging onto his back and wrapping his legs around him. Sensing Mazzulla’s struggle, Costa stresses that he does not teach this technique to novice students. It’s a sign he does not view Mazzulla as one.

“This is the hardest thing we’ve done,” Costa says. “Do not accept failure.”

Mazzulla hopes his jiu-jitsu training will help him keep the Celtics in the playoffs for a long run.Craig F. Walker/Globe Staff

It’s time to conclude the 90-minute class with a fight. This is what Mazzulla looks forward to most: struggling, progressing, studying, losing, and extracting useful lessons.

He walks over to his iPhone and turns on some R&B music. Costa sets a timer for the first of three rounds, and a robotic voice counts down the start.

Mazzulla quickly finds himself in a bad spot, and Costa can sense his frustration.

“You’re in a losing position,” he says. “You have to stay calm and not be mad at you, or me, or no one. That’s not going to help you.”

Mazzulla says he is not mad, but Costa says his actions say otherwise. The round ends and Mazzulla stops to ask Costa a few questions. Costa senses the stall technique and ushers him back into position for Round 2.

Mazzulla is expending plenty of energy, and it’s obvious. His moves appear almost frantic. He’s dripping in sweat and out of breath, and it’s unclear whether he’s having success. The timer buzzes and Mazzulla falls onto his back. He tells Costa he is finished.

“One more round!” Costa implores.

“No, I can’t.”

“One more. Don’t do that. Don’t kill the session.”

Mazzulla doesn’t respond, but his silence indicates that he will not quit. The final round begins and Mazzulla is invigorated. He slides around the mat with purpose and wraps up Costa with strong, precise holds. He is not trying to do too much.

Student and teacher have developed a special bond.Craig F. Walker/Globe Staff

The timer goes off and Costa is thrilled. He tells Mazzulla that when he’s fresh, he “acts like a crazy guy” trying to win a fight. In the last round, his fatigue forced him to focus.

“You’re a much better fighter when you’re tired,” he says.

“I just went into survival mode,” Mazzulla says.

Their session complete, Mazzulla leans down and kisses the sweat-soaked mat. Then he and Costa hug before Mazzulla leaves the windowless room and continues preparing for his even bigger challenge.

Adam Himmelsbach can be reached at [email protected]. Follow him on Twitter @adamhimmelsbach.

Source link