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To the Boston Celtics, their Game 3 loss against the Miami Heat in the Eastern Conference finals was nothing short of a catastrophe. Jaylen Brown described it as "embarrassing" and said that they had let their fans, their organization and themselves down. Coach Joe Mazzulla fell on the sword, repeatedly saying that he didn't have the team ready to play. 

But behind closed doors, another prominent Celtics figure said something, uh, surprising. 

From The Athletic's Jay King and Jared Weiss:

When the Celtics fell into an 0-3 hole in the Eastern Conference finals, everyone was at a loss for words postgame. But not Celtics managing partner Wyc Grousbeck, who cut through the silence of the visitor's locker room in Miami.

With the season on the line following a 128-102 Game 3 loss to the eighth-seed Heat, Grousbeck came in hot. After Grant Williams asked everyone to clear the room so the players could have some space, Grousbeck went off.

His message to the effect that he has been building this franchise for over 20 years and the players need to play with some balls left the locker room stunned, several team sources who were in the room told The Athletic. The sources were granted anonymity because they were not authorized to speak on the record.

Down 3-0 after a blowout loss, it is not unusual for anybody in the organization's emotions to be running high. It is unusual, however, for a team owner to chide players in that way. 

"(Grousbeck) was right, but we shouldn't need that," Blake Griffin told The Athletic. "As soon as we got to the locker room, we were just so frustrated."

Also unearthed by The Athletic: A meeting in March between Brown, Jayson Tatum and Mazzulla, in which the stars urged the coach to put Grant Williams back into the rotation. The story describes tension between several players and Mazzulla over his distribution of playing time -- by deemphasizing two-big lineups featuring Robert Williams and Al Horford and then by going away from Grant Williams, sometimes in favor of Sam Hauser, there was reportedly a sense that Mazzulla was focused on Boston's spacing at the expense of its defense:

Some of the players started to believe Mazzulla prioritized the offense too much, according to team sources. Several veterans wondered why the coaching staff went away from Grant Williams, who had a significant role in slowing down Kevin Durant, Giannis Antetokounmpo and Bam Adebayo on the way to the Finals last season. Still, in early March, he received his first DNP-CD since the 2020-21 season. Williams' playing time was sporadic from that point forward and he again fell out of the rotation when the playoffs began.

The coaching staff believed in Hauser's offensive production and felt that because opponents were going out of their way to target him and abandon their own offense, his ability to hold up decently in isolation made him impactful. Mazzulla also wanted to get Hauser more experience to prepare him for the playoffs, believing Williams would be ready to go if his number was called. But the team's veterans believed Williams would be crucial in the playoffs, so Tatum and Brown met with Mazzulla in early March to implore him to put Williams back into the rotation, team sources told The Athletic.

"The stars stepped up and told Joe what they wanted and Joe listened," a player source said.

In fairness to Mazzulla, the Celtics had the second-best defense and the second-best offense in the NBA during the regular season. I was as confused as anybody about the Williamses' minutes decreasing, but when Mazzulla pushed back on questions about Boston's defense by saying that the two ends of the floor are connected, I usually agreed with him. 

"Our strength is our offensive management," Mazzulla told reporters the day after the Celtics dropped the series opener against the Philadelphia 76ers in the second round. He added that they "have been built on defense for a very, very long time, they have the DNA in that and they're always going to play hard, but we manage the game best with our offensive decision-making." A day later, Boston won in a blowout and Mazzulla told reporters, "We just managed the game well: Our defensive presence led to our offense; our good offense led to our defense." 

After the Game 3 loss in Miami -- and after Grousbeck's locker-room speech -- Mazzulla went to the podium and said that "some of that defensive identity has been lost, and we have to get that back, and that's where part of that on me is to make sure we get that back." He added that, at their best, the Celtics are "connected, we're together, we're physical on the defensive end," but "we don't have that right now."

Even then, though, it was hard to disentangle Boston's mental mistakes on defense from its poor shooting. Missed shots, bad decisions and turnovers put pressure on the Celtics' transition defense, and there is a reason why you often hear players -- not just in Boston -- lamenting that they'd let missed shots affect their defense. 

In three wins against the Heat, the Celtics scored 120.9 points per 100 possessions and allowed 110.3 per 100. In four losses, they scored 106 per 100 and allowed 121.1 per 100.