“Everything he’s doing is in public,’’ Ainge said. “TV cameras are watching him cry. Even to this day, weeks later, it is still so public. So, you don’t really get this time alone to mourn the loss of a loved one. You’ve got to be in front of cameras.

“Isaiah handled himself unbelievably, in my opinion. After Game 2, I was talking with him before he went on his flight out to Washington. He was wondering if he should quit. All of these kinds of things were going through him because he was in so much pain.’’

Relive the Celtics storm back from 0-2 deficit to beat Bulls in first round.

Criticism in Boston was growing after Boston trailed 0-2 to the No. 8 Bulls - as if only the first loss was understandable, as if the three days should have been enough time for the Celtics to set aside life-and-death in order to focus on the ball and the basket. Of course, it was all backward. The critics were holding the Celtics to a standard that they would never apply to themselves. But Ainge and Stevens recognized and accepted why their team was losing – the Bulls were playing freely with joy, while the Celtics were trying to make sense of a tragedy that made no sense.

“You’ve got to give Chicago credit,’’ Ainge said. “But we were playing tight. Everyone wanted to win, but there was not a lot of emotion being shown. Nobody knew if you could laugh, if you could joke. You’re just trying to keep your distance, and how do you do that on a basketball court with millions of people watching you? How do you interact? It was an educational experience for everybody to go through that.’’

After the Game 2 loss, Boston’s longtime head athletic trainer Ed Lacerte received an impassioned voice mail from Garnett. Lacerte shared the recording with Ainge and Bradley, who had grown up playing AAU with Thomas.

“Eddie didn’t know if he should give it to Isaiah, because there were some personal things in there about Chyna,’’ Ainge said. “But I had Isaiah come in to listen to the message, because I think KG was sending it to Isaiah. And it was an inspirational message to Isaiah. Isaiah was very taken back by that and he immediately said, ‘I want everybody to hear this. I want the whole team to listen to this message from KG.’’’

Thomas played the voice mail from Garnett for the entire locker room to hear before Game 3 in Chicago.

“He took it in the spirit of how hard this is, losing your sister, but you have got to play for her, and the whole team has to play for her,’’ said Ainge. “It was a good message at a time that Isaiah was receptive to it. Maybe he would not have been receptive for Game 1 or Game 2. I think that was Isaiah’s way of saying to his teammates, ‘Come on you guys,’ but without him having to say it - it was someone else that all the players respect saying, ‘You’ve got to just play. You’ve got to play to win and you’ve got to play together and play for Chyna.’ And I think it was the turning point in that series.’’

Garnett’s fiery message enabled the Celtics to change their point of view. They appear to have shifted from mourning the death of Chyna Thomas to celebrating her life.

There is still much deference and respect for Thomas, and for the sadness that so often gets the best of him. But there is also a sense of unity and common purpose that has transcended the six games in a row that they have won – four against Chicago, and the first two in Boston against the Wizards.

“I was inspired by Isaiah and how he handled everything,’’ Ainge said. “Knowing what I know now of his closeness with Chyna, their upbringing and how much they were together, it was pretty inspirational for him to play the first game and the second game. And it was inspirational to see the guys who wanted to help Isaiah through it. At first it almost added pressure. But then once they got down 0-2, it was like our backs were to the wall and they came together. And that was impressive because Chicago is a good team. It’s not like we are this amazing team that’s automatically going to beat Chicago.

“I also felt after Game 2 that Isaiah was different,’’ Ainge went on. “A few days had gone by, and it was like, ‘I really want to be more inspirational and overcome this challenge. As hard as it’s going to be, I don’t want to be a burden.’ So, I felt like the team and him all were a little bit different when we got to Chicago. Isaiah came back into a more normal environment.’’

The 5-9 Thomas has, in turn, responded with some of his best games of the season: 33 points each in Game 4 at Chicago and then again in the opening comeback win against Wizards, to be followed by 53 points (29 in the fourth quarter and overtime) while Boston seized a 2-0 series lead over Washington on what would have been his sister’s 23rd birthday.

“I love Isaiah,’’ Ainge said. “He’s a fun guy with an infectious smile and great passion, and he loves to play basketball. But even if he had not dealt with this as admirably as he has, I’d still love him the same. The best thing that I see from this is that Avery and Jae Crowder and Al Horford and Amir Johnson and Jaylen Brown – they’ve all learned from Isaiah on how they should look to handle these kinds of things in life. They should look at it as, man, he handled that really well. Inevitably we are all going to have to deal with issues and challenges and trials in our life, and that is a good model that Isaiah really set for everybody that was a witness.’’

Horford could not agree more. He had been recruited by the Celtics to be their veteran leader, and yet he has experienced a lesson that will inspire him for the rest of his life.

“We didn’t know how to handle it,’’ Horford said. “I didn’t know how to handle it. I had never experienced anything like that. So, it was very quiet around here. Nobody wanted to talk. Nobody wanted to address anything. It was just all very awkward. But then seeing Isaiah a little more upbeat – that was important. It makes us feel better now that we see that he is getting back to being himself again, and we feel like we are starting to get it together as a group.’’

A quiet role model

It’s as if Horford has emerged as a steadying avatar for Stevens in the same way that Garnett used to reflect the blazing passion of his coach Doc Rivers, when they were together in Boston not so long ago.

“Ultimately what he does for your team - from the contagious unselfishness – is to give you a winning mindset,’’ said Stevens of Horford. “Wins are all that matters, and it becomes bigger than the stat sheet. That’s the way he’s been for a long time, which is one of the reasons why we wanted him here so bad. It wasn’t just because of what he can do statistically. It’s because he gets it, and it’s good to have a guy like that around all these young guys.’’

First year Celtics center Al Horford has been a steadying influence on young team.

Consider the journey of this young team. The best young Celtics have improved in no small part because Horford – widely talented and yet selfless - helped to create the winning environment in which they expressed and fulfilled themselves. And now, thanks to the recent emotional assist of his predecessor Garnett, Horford has been raising his standard all the more in the postseason.

After not knowing how to react to the death of Chyna Thomas, Horford has responded with a heightened level of efficiency that has laid the foundation for Thomas to close out with his prolific scoring. During the Celtics’ six-game winning streak in the playoffs, Horford was averaging only 10.5 shots – 1.3 fewer than during the regular season – and yet he was averaging 17.0 points while shooting 66.7%. In those games, he was also shoring up Boston’s rebounding deficiency with 9.0 boards while creating 6.5 assists (and just 1.7 turnovers). He was pushing the ball upcourt in transition and anchoring the defense of big and small lineups alike. Through eight playoff games overall he was converting 47.4% from the 3-point line.

Instead of focusing on scoring and/or rebounding to the exclusion of all else, Horford was playing a winning hand in every phase of the biggest games. He was making more of his diverse range of talents than ever.

“He’s one of the best at his position, if not the best,’’ said Wizards coach Scott Brooks of Horford’s passing as a big man. “If you are looking at the numbers, you’re probably going to be looking at the wrong things. He makes winning basketball plays. He does all the intangibles that it takes to have a winning team, and he exemplifies that night in and night out. If he really wanted to be a 20-point scorer, I’m sure he can. But he cares about winning only.’’

By Horford’s example, the younger Celtics have seen that those winning plays are far more valuable than the accumulation of individual stats. Horford very easily could have led them down the wrong path this season by exploiting the power of his contract to demand extra touches and a higher individual scoring average – in which case the Celtics never could have bonded as they have over the last fortnight. Because they never would have learned to trust in one another.

“It’s certainly not like 2008,’’ said Ainge of the postseason when Garnett’s Celtics won the championship. “Or 2009, when we lost KG (to injury) but we started out 27-2. Those were very, very special teams. This team is not them. But it has been a very rewarding year. It’s just fun for some of these guys to have the kind of success and attention that they’ve never had.’’

Horford, like Garnett before him, takes pride in the attention that has been earned by his teammates, even if their success has resulted in complaints about him. From the depths of their recent misery, win or lose this series against the Wizards – who ended Boston’s winning streak with a 116-89 win Thursday in Game 3 – the Celtics have established an identity that may draw them together long after their careers have ended.

“I do believe, based on the things that we have been able to accomplish and how we are playing now, it has to be one of my better seasons,’’ Horford said. “But the year isn’t over yet, and I really don’t want it to stop.’’

Ian Thomsen has covered the NBA since 2000. You can e-mail him here, find his archive here or follow him on Twitter.

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