BOSTON (WPRI) — The Boston Celtics removed Joe Mazzulla’s interim tag on Thursday, making him the 19th head coach in franchise history.

The Johnston native and former Bishop Hendricken star also agreed to a contract extension, but the terms of the deal were not disclosed.

“As he has shown, Joe is a very talented coach and leader,” said Brad Stevens, the Celtics’ president of basketball operations. “He has a unique ability to galvanize a room around a mission. We are thankful for the work he has done to help get us to this point, and excited that he has agreed to lead us into the future.”

Mazzulla, 34, took over as interim head coach in September when Ime Udoka was suspended for violating team policy.

The Celtics are heading into the All-Star break with the best record in the Eastern Conference at 42-18.

Mazzulla, the NBA’s youngest head coach, will coach Team Giannis at the All-Star Game in Salt Lake City. He is just the third rookie head coach in the past 24 seasons to coach an All-Star team, and the eighth Celtics coach to earn the honor.