It was a small gesture with a big impact.
"My eyes were so wide, to get that T-shirt was unbelievable," Ujiri said.
Ujiri speaks passionately about the power of sports to change lives. He's seen it first-hand through his Giants of Africa camp and Basketball Without Borders, and is himself living proof as the president and general manager of the Toronto Raptors.
It's a determination he shared with the late Nelson Mandela, who Ujiri and the Raptors will celebrate Friday in an all-star benefit.
"How many people in those kinds of positions ever have any kind of relations with sport in some ways other than being like a guest of honour or something?" Ujiri said in a phone interview Thursday.
"But Nelson Mandela, with what he did with rugby, the way he supported sports, I thought it was so impactful because he said it best: sports has the power to impact people and society, and youth. And so I think it's a great message for us, it's not only a great game, but it's a great day to spread that message around the world that we are blessed to have sports and we are blessed to participate in something fun like this."
When South Africa won the 1995 Rugby World Cup, Mandela famously donned the Springbok sweater, a gesture he hoped would help unite his racially-fragmented country.
Friday marks the one-year anniversary since Mandela's death at the age of 95.
Ujiri has assembled an all-star lineup for the event, including NBA legends Charles Barkley, Magic Johnson and Dikembe Mutombo, along with UN Goodwill Ambassador and 1999 Miss Universe winner Mpule Kwelagobe. Other guests include Raptors alumnus Tracy McGrady, Toronto Maple Leaf goaltender Jonathan Bernier and Leafs president Brendan Shanahan, former Toronto Argonauts star Michael (Pinball) Clemons, deputy commissioner of the NBA Mark Tatum and Amadou Fall, vice-president of NBA Africa.
Funds raised will go to both the Nelson Mandela Foundation and Ujiri's Giants of Africa.
Ujiri founded Giants of Africa in 2003, both as a means to enrich the lives of children in Africa, and to shine a spotlight on the abundance of untapped talent there.
He signed a deal with Nike to outfit the players. He sees himself in the kids he helps.
"You see these kids, their faces when you give them shoes and you give them gear, socks and shorts and jerseys and T-shirts, it's remarkable how that affects them in some kind of way, and how they want to play the sport more, and even dedicate themselves more," Ujiri said. "But it's come to a point where I look at myself, and say: We have to look at it even beyond playing. I say 'How do we really use basketball as a tool?' Because now sports has become so general, it's important to expose Africa and kids to other aspects of sport.
"What about sports medicine, and sports journalism, and sports agencies, coaching, and all the different things that you can do in sports," he said. "It doesn't have to be making the NBA or it doesn't have to be playing. You can figure out how you can use basketball as a tool and guidance to maybe do something very very reasonable and very very good for your life, and to grow.
"It doesn't necessarily have to be playing basketball. I'm the prime example of that."
The six-foot-four Ujiri played basketball in the U.S. at Bismarck State College, and then spent six years playing professionally in Europe. He virtually chiselled out a post-playing career for himself, working as an unpaid scout for the Orlando Magic. He paid his own way on trips at times, and bunked with other scouts and players.
He went on to be an international scout for Denver and Toronto, then won NBA executive of the year in 2013 with Denver, where he was the first African-born GM of a major North American sports team. He returned to Toronto to be the team's president and GM in 2013.
Ujiri said his summer trips to Africa are the times he looks forward to most.
"Going spending it in the grinds of not only travelling in Africa and seeing different cultures and different people, but seeing different communities and people, and what makes them tick and what makes them live, and how they live happy, and some of the struggles that they have. It puts life in perspective," Ujiri said. "It's a huge part of who I am and what I want to do.
"Our concentration is sports and how we can build sports, and going into communities to help, whether it's teaching basketball, whether it's us figuring out charities or foundations that we can help, or us figuring out little courts that we can build, or give them a net, give a basketball team basketballs . . . those are the things we want to continue to build and grow over there. That's the impact it has on me when I go back in the summer," he said.
A big believer in never forgetting where you've come from, Ujiri said his experiences in Africa remain with him in his daily work back in Toronto with the Raptors.
"Honestly, it puts things in perspective," he said. "We take things for granted a lot of times, and I would never forget to be humbled by the position that I am in, and the blessings that I have to be in this position, with such good people around me that give me that opportunity to go help other Africans, and other youth.
"I have to be a voice, and I have to make an impact on other people. If not, what I'm doing here means really nothing."
Friday's celebration will begin with a panel discussion. It will continue into Friday's Raptors game versus the Cleveland Cavaliers, with video tributes. The Raptors will wear special edition shooting shirts and management will don Giant of Africa lapel pins. "The Giant of Africa" T-shirts will be for sale, featuring Mandela's five pillars; being a leader, fighting for freedom, creating a better future, committing to the community and using sport to inspire change. Proceeds from sales go to Giants of Africa.