It was the day after the public unveiling of the spectacular new Celtics practice facility in Brighton one month ago when Marcus Smart and Kenny Boren decided to take a detour through town to check out the Red Auerbach Center in person.


Boren, Smart’s high school coach and director of his YounGameChanger basketball camps, said they thought they were in there alone as they sorted through all the bells and whistles of the state-of-the-art facility when a familiar face came over [...]

It was the day after the public unveiling of the spectacular new Celtics practice facility in Brighton one month ago when Marcus Smart and Kenny Boren decided to take a detour through town to check out the Red Auerbach Center in person.

Boren, Smart’s high school coach and director of his YounGameChanger basketball camps, said they thought they were in there alone as they sorted through all the bells and whistles of the state-of-the-art facility when a familiar face came over and surprised the impending restricted free agent.

“Coach (Brad) Stevens snuck up behind him and it was kind of funny,” Boren said. “He was there showing it off to his family and they wound up spending about 20 or 30 minutes talking with each other. It was a cool moment.

“They have a very special relationship. Marcus loves Coach Stevens – I don’t know anyone who would say they don’t love Coach Stevens – but there is a definitely a mutual respect there. That’s the type of stuff that shows Marcus how much they appreciate him there. That’s why when (free agency) started (July 1) he was like: ‘C’mon man, I want to get this (new deal) done soon.’”

After three weeks of waiting, with some frustration at times, Smart got his new deal with the Celtics on Thursday when he agreed to a four-year contract reportedly worth about $52 million. Boren confirmed it was a done deal as he texted with Smart Thursday morning and said the 24-year-old guard is “thrilled” to be staying in Boston.

The team made it official in the afternoon, and a press conference was scheduled for 4 p.m., but then postponed because Smart experienced stomach flu-like symptoms and was receiving IV fluids at New England Baptist Hospital, the Celtics announced.

“He’s a happy man,” Boren said. “Everyone seems happy with it. I know Marcus is happy. It played out perfectly and he got a fair deal.”

Boren said Smart, whose mother, Camellia, is battling bone marrow cancer, will benefit from the “stability he needs right now” that comes with the long-term deal after a few weeks of uncertainty when it was reported he was “hurt and disgusted” by the lack of outreach from the Celtics.

“He’s an emotional guy who has been through so much in the last six months,” Boren said. “When it came out that he was disappointed – I’m not sure he said ‘disgusted’ – with the Celtics it was a time where he was going through a barrage of emotions. He was moving his mother from the house in Flower Mound (Texas) to an apartment across from where she’s getting her treatments. He’s literally moving beds, so he was antsy. He had a lot going on those couple of days.” 

Boren said Smart spoke extensively with Celtics president of basketball operations Danny Ainge over the past week leading up to the agreement.

“This was the first big contract of his career so it was new to him,” Boren said. “In the end both sides came together and they made a very, very fair offer. Marcus is thrilled.”

Smart came out the day after the Game 7 Eastern Conference finals loss to the Cleveland Cavaliers and declared his desire to stay with the Celtics and the city of Boston where “they show you the love that you show them.”

He reiterated that desire at his basketball camp at Brandeis University in Waltham on June 21.

“Boston has shown me so much love in my years since year one,” he said. “You always want to give back to the city you love because it’s hard to find people, things, anything that really cares about you, or that you care about, that’s genuine. Boston is a genuine place.”

Now he will get to stay in that genuine place as the longest-tenured Celtic for the foreseeable future.

“No one has ever coached Marcus on what to say and when to say it,” Boren said. “When he is in front of the cameras he speaks from his heart. He is blunt. He doesn’t BS. Sometimes that’s good. And sometimes it backfires. 

“But he’s always been up front about how much he loves Boston, and especially loves his coaches and loves the fans. Of course, that is something special to him.”