A week or so after the Celtics were eliminated from the playoffs by the Knicks, president of basketball operations Brad Stevens said coach Joe Mazzulla had multiple years left on his contract, although Mazzulla appeared to be entering the final year of his deal.
Perhaps Stevens was hinting that an extension was a foregone conclusion, and sure enough, the sides announced Friday a multiyear deal.
Mazzulla was named interim coach, replacing the suspended Ime Udoka, in September 2022, and then signed a three-year deal in February 2023, when the interim tag was removed. The Celtics have had great success in Mazzulla’s three seasons, with a run to the Eastern Conference finals, a championship, followed by the second-round elimination to the Knicks, partly because of injuries.
The Celtics have been thrilled with Mazzulla’s growth as a coach and impact on his players.
“This is truly a blessing,” Mazzulla said in a statement. “I would not be here without my faith, my wife, and my children. We are thankful for the partnership with our ownership groups, Brad’s mentorship, and the support of our staff. Most importantly, I am grateful for the players I have been able to coach the past three seasons. I look forward to competing for the Celtics and the city of Boston.”
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Mazzulla, 37, joined the Celtics in 2019 as part of Stevens’s coaching staff, and then coached under Udoka, before making the stunning move from behind the first row of the bench to the head coaching position. Mazzulla has emphasized 3-point shooting, ball movement, and spacing, and in 2024 completed a historic season by going 16-3 in the playoffs and finishing with a plus-11.34 point differential, sixth highest in NBA history.
“We are very excited that Joe has agreed to extend with the Celtics,” Stevens said in a statement. “He understands the job and has a passion for the Celtics that is only rivaled by our most die-hard fans. He’s worked hard and accomplished amazing things in his first three years as a head coach — including averaging over 60 wins per season and winning the 2024 NBA championship. Joe is a gifted leader who brings a consistent commitment to learning, improving, and maximizing each day we get to compete for the Boston Celtics.”
The 2025-26 season may be the most challenging season yet for Mazzulla, with Jayson Tatum expected to miss at least most of the season recovering from a torn Achilles’, and with Kristaps Porzingis and Jrue Holiday traded to clear salary-cap space and the restrictions of the second apron. For the first time in Mazzulla’s career, the Celtics will enter a season not favored to reach the NBA Finals.
Gary Washburn is a Globe columnist. He can be reached at gary.washburn@globe.com. Follow him @GwashburnGlobe.