Joe Mazzulla remains head coach of the Boston Celtics and will return next season, team president Brad Stevens said Thursday.

"He's a terrific leader," Stevens said. "He'll only get better at anything that he can learn from this year, because he's constantly trying to learn. And he's accountable."

Mazzulla, 34, led the Celtics to a 57-25 record and the No. 2 seed in the Eastern Conference in his first season on the bench. Boston's season ended Monday with a Game 7 loss to the Miami Heat in the East finals.

Mazzulla took over when coach Ime Udoka was suspended for the season in September for multiple violations of team rules. He reportedly had an intimate relationship with an unidentified female staff member.

Three Celtics assistant coaches -- Ben Sullivan, Aaron Miles and Mike Mose -- are reportedly leaving to rejoin Udoka, who was named head coach of the Houston Rockets last month.