BREAKING NEWS: Earlier Today BOSTON CELTICS head of coach Joe Mazzulla. Who took over the team on February 16, 2023, becoming the 19th head coach in Celtics history. he finally announced and submitted his resignation letter due to… see more.

In a stunning turn of events, Boston Celtics head coach Joe Mazzulla has officially announced his resignation earlier today, submitting a formal letter to the team’s front office. The news comes as a major surprise to both fans and league insiders alike.

Mazzulla, who took over the Celtics on February 16, 2023, became the 19th head coach in franchise history, guiding the team through two highly competitive NBA seasons. Under his leadership, the Celtics maintained a strong playoff presence, continuing their legacy as one of the league’s most dominant teams.

While the Celtics have yet to release a formal statement, sources close to the organization say Mazzulla cited “personal and professional differences with upper management” and a desire to step back from coaching to prioritize his mental health and family.

Team President Brad Stevens is expected to address the media later this evening.

This sudden departure leaves the Celtics in urgent need of a replacement ahead of the 2025–2026 NBA season. Speculation is already swirling around several high-profile candidates, including current assistants and former NBA head coaches.