Marcus Smart went out to the court before a Celtics game for the first time about 20 minutes before tip-off on Sunday. From the visitor’s tube, he did this. It was so loud in the crowd that Smart could barely hear himself wave back.

What happened after thirty minutes was a lot worse.

The crowd stood during the first break of the first quarter for a tribute that had been a long time coming and was well-earned. On the video board, a two-minute movie played. It showed the plays that made Smart one of the most popular Celtics players in the past few years.

When the video tribute was over and the camera went to Smart, Jayson Tatum, who was sitting on the Celtics bench, told the crowd to speak up. It looked like he was moved. He pumped his chest a few times. He blew kisses to everyone in the crowd and then put out both arms to meet them. He worked here for nine years. People in the crowd yelled, “We love Marcus!”

Smart told them ahead of time, “I love you guys and will always have a place in my heart for you.” Boston’s always going to be here. “Don’t forget.”

Last month, Smart hurt his right ring finger and is still healing. That’s why he didn’t play on Sunday. He was a team icon for nine years and a fixture in Boston, and his comeback was perfectly captured by the Celtics.

It summed up Smart’s play as one of the league’s best defenders and hardest opponents. He played a big role in the Celtics getting back to the top of the Eastern Conference. He was also named a “Hero Among Us” for his community service. For nine years, he visited kids with cancer at Boston Children’s Hospital every day and started the YounGameChanger Foundation to help student-athletes from big towns.

“I’m proud to be more than just a basketball player,” Smart said. “I think being here in Boston has really given me a chance to show who I am as a person.”

It came as a surprise when Smart quit in June. He was traded to the Grizzlies just before midnight on June 21. Smart didn’t learn about it until the next morning. He was angry about this because, as he explained, the group had told him a week before that they would not sell him.

Smart got over it eventually. He said that getting married and other big life events in the past year helped.

Smart said, “it didn’t hurt as bad as I thought it would.” “I know this business and I know business in general.” People still ask me if I would make the same business choice if it were my own. They just told me, “Hey, here you are after nine years. Let me know what’s going on.” “This is what’s happening.” That’s great.

“In the end, I’m also a businessman.” That’s where the hurt came from. But, as I said, I was able to forget about it. There is no bad blood between me and the organization, my friends, or the coaching team. I love each of you. I’m glad I got to play with those guys.

After his morning news conference, Smart went to the Celtics locker room to see some old teammates. The guard is happy with how well the Celtics have done without him. He wishes he could have helped them win a championship, but he’s happy to see them keep doing well, especially Tatum and Jaylen Brown.

Smart said, “It’s amazing to see my brothers doing what they love to do and doing so well at a very high level in every sport, but especially with this group of guys.” It’s been great getting to know these guys. Over the years, I’ve seen them deal with a lot of abuse. For them to finally get it together is what I want. I loved seeing it every day. You guys were lucky to see it for a short time on the basketball court. I’m so happy for those guys. …

Smart said it would be hard to understand why they weren’t going on the trip with them. “But, like I said, it doesn’t change how I feel about good guys at the end of the day. I think they deserve it just as much as I do.”

Smart always loved Boston and the Celtics, no matter what time of day or night it was. This will always be the same, no matter what he does for a living.

Smart said, “I feel like Boston is a second home.” “I could talk all day about what I’ve seen and done here, but what struck me was how Boston welcomed me.” I’m the one who usually tells them that it’s not easy to play here, so everyone knows that. But this place is always great, and I can speak for everyone who has played here, even the other team. When you play in this place with these fans, there’s nothing better.

“They made me feel better.” They saw a different side of me and watched me grow up. And my best things have changed my life in many ways. They will always be here.