They were drinking apple cider, taking selfies, and watching President Joe Biden execute a pump fake. But, Friday night against the young and unestablished Wizards, the Celtics got off to a sluggish start.

Could you feel that?” Mazzulla said. "It wasn't really about energizing the team, it was really about manipulating the environme

After ending the Cavaliers' unbeaten season, Joe Mazzulla expressed what he likes about the matchup for the Celtics.

I’m not talking to you during the season. I’m not waving to you at the national anthem. I’m not doing that. You’re an enemy.”

The Boston Celtics are set to take on the Toronto Raptors in their 14th game of the young season on Saturday. The Celtics sit with a 10-3 record and will look t

Celtics head coach Joe Mazzulla knows that even friends can be a distraction at times, and he explained how with a story about a hug.

Charles Lee won a championship as the lead assistant on Joe Mazzulla's staff with the Boston Celtics last season. When Lee left to become the coach of the Charlotte Hornets, Mazzulla informed Lee that he was now the "enemy" and shouldn't expect to chat like they did when they were on the same side.

Joe Mazzulla has been a quote machine since taking over as the Boston Celtics' head coach. Here is a collection of his most memorable soundbites.

But when it comes to Boston Celtics head coach Joe Mazzulla, a very different approach to physicality is evident. Not only does Mazzulla not eschew physicality for his stars, he seeks it out up and down the roster.

Boston Celtics coach Joe Mazzulla was called for a technical foul in the third quarter of Friday night's win over the Washington Wizards. The foul, seen below, was assessed to Mazzulla as he was being held back from referees by assistant coaches Tony Dobbins and Sam Cassell.