WALTHAM -- The most touching moment of an emotional Boston Celtics-Chicago Bulls Game 1 took place hours before tip-off.

After putting up some pregame shots Sunday, Isaiah Thomas sat down on one of the courtside chairs and broke down. His younger sister, Chyna, had passed away the previous day in a tragic car accident. With the playoffs starting, Thomas had no time to step away and deal with the pain. Part of his grieving unfolded with TNT cameras rolling.

Charles Barkley later called the scene "uncomfortable" to watch. The analyst also said some other things about the moment, few of which seemed particularly insightful or understanding. But uncomfortable? Yes. Death shakes a person's world. There is nothing comfortable about watching someone with a shattered heart.

Avery Bradley saw his teammate suffering. During the short clip televised, Bradley did not say a single word. He just sat next to Thomas with an arm around Thomas' shoulder. The gesture didn't help much. It couldn't. But Bradley did what he could.

"We can say whatever to him, but I think our actions really let him know that we care for him," explained Bradley. "It's just a sanctuary being on the basketball court, so for us to be able to make him feel happy and make him feel like we have his back, I feel like as brothers that's what you're supposed to do."

.@3DTV reports on Isaiah Thomas from Boston. pic.twitter.com/W7a1TWZwpc — NBA on TNT (@NBAonTNT) April 16, 2017

Bradley's respect

For 15 years now, Bradley has admired the lefty who never stops getting buckets. Bradley and Thomas both grew up in Tacoma, Wash., and played for the same AAU organization, then called the Icemen. As a young kid, maybe 11 or 12 years old, Bradley can recall sitting in the stands, dazzled, as Thomas split defenders, bounced off centers, and finished over kids who looked at least three or four years older than he did.

Bradley's friends idolized Thomas, too.

"Isaiah was two years older than us," Bradley recalled earlier this season, "so he was who we all looked up to."

In the close-knit Seattle-area basketball scene, Bradley and Thomas developed a friendship over the years, then grew tighter after becoming teammates two years ago.

Their bond matters now more than ever.

"I think that's really important," head coach Brad Stevens said. "Avery obviously being from Tacoma and knowing Isaiah and his family for a long time. I think that's been a big deal for Isaiah."

"Me and Isaiah have known each other since we were kids," Bradley said. "So we're just family. And no matter what goes on we're always going to have each other's back. We're always going to be there for one another. And I think he knows that and I know the same about him. We're always going to support each other. Not to say our teammates aren't going to support us as well, but we're family so it's different. I'm going to be there for him no matter what. I'm just happy to be a part of his life. He's a special person, special player, and I know that as this playoff series continues Isaiah's going to continue to play well. And I'm going to continue to support him. And he's going to play for his sister."

Thomas 'doing it by his actions'

Thomas hasn't talked as much since his sister's death. Even while scoring 33 points in Game 1, he never reacted like he normally does, with a finger pointing at his wrist, a muscle-flexing celebration, or the roar of a tiny lion. None of his teammates would ever blame him for failing to show his usual vibrance. They understand he needs to deal with the grief however is best for him. But they have noticed the difference, and they are in awe Thomas can give what he has.

"He's doing it by his actions," Bradley said. "Isaiah's coming out, he's playing hard. And it takes a lot of balls for somebody to go through that and still be able to come out and perform at a high level. Even though he wasn't screaming or the usual Isaiah, he still went out there and fought hard. And it made us want to fight harder for him. We just made some mistakes that are fixable and we'll have a chance to do it (during Game 2)."

"I think the biggest thing is that they really care about each other," added Stevens. "I said this before the game: It's really tough when he's sitting there, and some of his family's back in Seattle, and some of them came here to mourn with him. I think the next extension of your family is who you're around every day, your team, and so these guys are really terrific teammates. They care about one another and they support one another. Obviously that's what you'd hope you have in a team. It's probably not always the case."