Joe Mazzulla isn’t one to wear his emotions on his sleeve-at least not often. But over the past week, the Boston Celtics head coach has shown a little more fire than usual, and it’s caught the attention of fans and media alike. During a recent loss to the San Antonio Spurs, Mazzulla slammed a clipboard on the sideline, a rare outburst from a coach known more for his calm demeanor than sideline theatrics.
Then came Monday night’s narrow 98-96 loss to the Indiana Pacers-a game that ended not just with frustration on the scoreboard, but in the postgame press conference as well. Mazzulla answered six consecutive questions with the same two words: “illegal screen.”
No elaboration. No added context.
Just a pointed, repeated phrase that clearly referenced a late-game play that didn’t sit right with the Celtics’ head coach.
Naturally, the moment went viral. Was it sarcasm?
Protest? A message to the league?
Mazzulla later addressed the reaction, brushing off the idea that he was overly frustrated and instead framing his terse postgame responses as intentional and controlled.
“That’s me looking frustrated? I’m in good shape,” Mazzulla said when asked about the exchange.
“I just kind of kept it to a simple one-word answer. So if you guys label that as frustration, I appreciate that.
That’s good.”
He went on to clarify that the message he delivered publicly wasn’t the same one he shared with his team in the locker room. For Mazzulla, the real issue wasn’t just the officiating-it was Boston’s third-quarter lapse that allowed Indiana to build a 13-point cushion, a run that ultimately proved too much to overcome.
“That message is much different than the message to our team,” he said. “The message to our team is the third-quarter run that they went on to get it to 13 points. That’s the most important thing.”
And he’s not wrong. In a league where games are often decided by a handful of possessions, letting momentum swing that drastically in the third quarter can be the difference between a win and a loss. Mazzulla emphasized the need to clean up both ends of the floor-offensive and defensive execution down the stretch remains a focal point for a Celtics team with championship aspirations.
“An NBA season is a long time,” he added. “There’s always moments of relaying a message or whatever the case may be.
But the message to our team today was we’ve got to clean up that third-quarter run. We’ve got to clean up our end-of-game execution, whether it’s on offense or defense.
And execution is different in so many ways.”
While Mazzulla may have kept his postgame comments short, the NBA offered a bit more detail. On Tuesday, the league issued its Last Two Minutes Report from the Celtics-Pacers game, confirming that Mazzulla’s frustration had some merit. The report noted that Indiana’s Pascal Siakam did, in fact, commit an illegal screen late in the game-a missed call that could have impacted the final sequence.
“Siakam is late to establish a screening position in White’s path and does not give him the time or distance to change direction and avoid the contact during the pick,” the report stated.
It’s the kind of late-game officiating error that can swing emotions and outcomes, especially in a tight, playoff-style battle like the one Boston and Indiana waged. Still, Mazzulla isn’t letting the missed call define the loss. His focus remains internal-on the film, the execution, and the moments where his team let the game slip away.
Despite the recent stumbles, the Celtics are still in a strong position at 24-15. They’ll look to regroup and refocus when they return to the floor Thursday night against the Miami Heat-a matchup that always brings playoff-level intensity.
For Mazzulla and the Celtics, the message is clear: clean up the execution, stay locked in, and let the rest take care of itself.