WASHINGTON, D.C. — Nickeil Alexander-Walker remembers his first encounter with a young R.J. Barrett in the Mississauga, Ontario, area when Barrett was just in sixth grade.

"He was the same but just not as developed," Alexander-Walker told me here Thursday in the Virginia Tech locker room at Capitol One Arena. "Very dominant for his age, scoring and affecting the game. Athletic, way more athletic than kids then. I think he was dunking or something crazy."

Barrett and Alexander-Walker will go head-to-head in a battle of Canadians when their teams meet here Friday night in the Sweet 16. When the Big Dance began, there were 24 Canadians in the tournament. Gonzaga's Brandon Clarke, a native of Vancouver, has already booked a ticket to the Elite Eight after the Zags beat Florida State Friday night.

"It's been like an invasion of talent," Duke coach Mike Krzyzewski said Thursday when I asked him about the Canadians. "And not just of talent but character."

The 6-foot-7 Barrett is projected as the No. 2 pick in the upcoming NBA Draft behind teammate Zion Williamson, and Coach K believes he can be among the best Canadians ever to play in the NBA. That includes two-time NBA MVP Steve Nash, Barrett's Godfather, and Minnesota Timberwolves forward Andrew Wiggins, the No. 1 pick in 2014.

"R.J. can be as good as anybody coming from Canada," Coach K.

"R.J. should still be in high school. He reclassified. And for him to have the maturity and talent to play at this level and what he's done, he's scored about 800 points. And he's been with us the whole time. He's the one kid that hasn't been injured."

Barrett and Williamson have become best friends during their time at Duke, with Zion saying on Thursday, "I love him. He's my brother."

Best buds RJ and Zion pic.twitter.com/KQ39Y4ay8Z

— Adam Zagoria (@AdamZagoria) March 28, 2019

Williamson went out of his way to say that although he got a ton of attention for his dunk from the foul line in Toronto back in August, he was upset because Barrett had done the same dunk and not received similar attention.

"R.J. literally took off from the free throw line like two seconds before me, but people wasn't giving him credit for that," Williamson said. "And I didn't want to be the guy to take away light from other players.

"And I said when people started giving my teammates the respect that they deserve, then I guess I'll start doing more stuff like that. But it hasn't really changed."

Zion out here now with his teammates as practice starts pic.twitter.com/5XrM1AgdQm

— Adam Zagoria (@AdamZagoria) March 28, 2019

Williamson and Barrett seem to always be together, and can often be seen laughing with one another, on the court and on the podium during interviews.

"It's funny, because I know what he's thinking and what he's about to say before he says it," Barrett said.

"But it's just great to have somebody you can relate to off the court. And I watch everything that he goes through and what goes on with him. And definitely kind of he's helped me a lot. And just amazing to have a brother like that."

The last Canadian to win an NCAA championship was Kyle Wiltjer, who did so with Kentucky in 2012. Before that, Denham Brown won in 2004 (UConn), Dave Thomas in 2000 (Michigan State), Jamaal Magloire in 1998 (Kentucky) and Mike Brkovich in 1979 (Michigan State).

Now Barrett wants to be the next one to do so before heading off to the NBA with his buddy Williamson. First he has to get past another Canadian in the Sweet 16.

"It's definitely great going up against Nickeil," Barrett said, "growing up playing against each other and definitely showing that Canada has some good players and that we're on the rise."

Adam Zagoria is a Basketball Insider who runs ZAGSBLOG.com and contributes to The New York Times. Follow Adam on Twitter.