Joe Mazzulla has built a reputation as one of the NBA’s most unconventional and driven coaches, and that approach extends well beyond the basketball court. As the Boston Celtics prepare for the 2026-27 season, Mazzulla is once again spending his offseason immersed in a different competitive environment.
Recent footage shared by MMA journalist Ariel Helwani showed the Celtics coach training at Xtreme Couture in Las Vegas, one of the most respected mixed martial arts facilities in the world. The videos featured Mazzulla participating in striking drills and grappling sessions under the guidance of renowned coach Eric Nicksick.
For many coaches, the offseason is an opportunity to disconnect from the demands of an 82-game schedule. Mazzulla, however, has consistently embraced challenges that test both his physical and mental limits, viewing them as an extension of his professional development.
That mindset has helped establish him as one of basketball’s most successful young coaches. From his rapid rise through the Celtics organization to his championship success in Boston, Mazzulla has repeatedly demonstrated that growth and preparation remain central to his philosophy.
1. Finding Lessons Beyond Basketball
Mazzulla’s interest in combat sports is far from a recent development. He has practiced Brazilian jiu-jitsu and participated in MMA training for nearly five years, making it a regular part of his lifestyle during both the season and the offseason.
Even during the NBA schedule, Mazzulla often visits local training facilities while traveling with the Celtics. His commitment reflects a belief that leadership skills can be developed in a variety of environments, particularly those that require discipline and adaptability.
Over the years, Mazzulla has openly discussed the similarities he sees between coaching and combat sports. He frequently points to qualities such as composure under pressure, preparation, and resilience as essential traits shared by elite fighters and championship teams.
Those principles have become embedded within Boston’s culture. Players have often described Mazzulla as a coach who challenges conventional thinking, encouraging his teams to embrace discomfort and remain mentally prepared for difficult situations.
2. A Partnership Built on Preparation
Mazzulla’s relationship with Eric Nicksick has become an important part of his development away from basketball. Nicksick, widely regarded as one of MMA’s leading coaches, has worked with numerous championship fighters throughout his career.
Their collaboration extends beyond physical training. According to those familiar with their relationship, the two frequently discuss leadership, preparation, and decision-making in high-pressure environments—topics that are relevant regardless of the sport.
The exchange of ideas has provided Mazzulla with a unique perspective on coaching. Whether preparing for an NBA playoff game or observing how fighters approach competition, he has consistently sought lessons that can be applied to his role with the Celtics.
By continuing his training this offseason, Mazzulla is reinforcing a message he often communicates to his players: improvement is a continuous process. The standards he sets for himself are the same standards he expects from those around him.
3. Building an Impressive Coaching Legacy
Mazzulla’s dedication has translated into remarkable success on the sidelines. After joining the Celtics as an assistant coach in 2019, he was unexpectedly elevated to interim head coach in 2022 before eventually securing the position permanently.
His tenure has quickly become one of the NBA’s standout coaching stories. In 2024, he guided Boston to an NBA championship, becoming the youngest head coach to win a title since 1970 and cementing his place among the league’s brightest coaching minds.
The accolades continued in 2026 when he was named NBA Coach of the Year. The recognition came despite a season complicated by injuries, including Jayson Tatum’s Achilles setback, which forced Boston to adjust throughout the year.
Through both regular-season and postseason competition, Mazzulla has compiled a 274-111 career record, giving him the highest winning percentage among coaches with at least 200 games coached. His achievements suggest that his unconventional methods may be contributing to one of the NBA’s most successful coaching careers.