Duke's Zion Williamson  celebrates after Blue Devils defeated the University...

Duke's Zion Williamson  celebrates after Blue Devils defeated the University of Central Florida in the second round of the NCAA Tournament at Colonial Life Arena on Sunday in Columbia, S.C. Credit: Getty Images/Kevin C. Cox

WASHINGTON — The biggest upset of the NCAA Tournament so far happened in a news conference Thursday. Who could have seen this coming? Someone with solid inside knowledge actually said Duke’s Zion Williamson is underrated.

Yes, the No. 1 celebrity in college basketball, the phenom whose dunks made him an international sensation when he was in high school, really is even better than people think he is. So says RJ Barrett, who knows Williamson better than anyone as his teammate, roommate and fellow freshman projected to go high in the 2019 NBA Draft.

“He does so many things on the court that people don’t really appreciate enough,” said Barrett, who hit the winning putback in the Blue Devils’ heart-stopping victory over the University of Central Florida on Sunday. “It’s definitely a lot of fun playing with him. He does some amazing stuff. In the UCF game, somebody was guarding me, I couldn’t see. I just threw the ball up anywhere and he just jumped up and got it.”

The top-seeded Blue Devils recognize they will have to be improved when they face Virginia Tech in the Sweet Sixteen on Friday night after Michigan State plays LSU in the other East Regional semifinal. Virginia Tech beat Duke, 77-72, when Williamson was out with a knee injury caused by a mishap with his sneaker (even his injury had a larger-than-life aspect).

“Yeah, he’s a tremendous player, but it is what it is,” said Virginia Tech swingman Ahmed Hill.

In terms of garnering attention, the season has gone as planned for the 6-7, 285-pound Williamson, who was named for Mount Zion in Jerusalem. The name was conferred by his mother, Sharonda Sampson, a former Livingstone College sprinter, at the suggestion of her mother, who thought the baby was destined for big deeds. Williamson developed point-guard skills under his stepfather, Lee Anderson, a former Clemson guard, before a growth spurt took him from a 5-9 eighth-grader to 6-6 high school sophomore.

Williamson began dominating this college season last summer, during Duke’s tour of Canada, with a dunk from the foul line during practice.

“I liked it, but then I also didn’t like it — that’s why I really haven’t done it since — because RJ literally took off from the free-throw line like two seconds before me, but people weren’t giving him credit for that,” he said Thursday. “And I didn’t want to be the guy to take the light away from other players.”

He can’t help it. He is the consensus No. 1 player in the country, and his 57 points last week tied Kevin Durant for the most ever by a freshman in the first weekend of March Madness. He is a social media megastar (Said Barrett, “The question you should be asking me is how do I get him to follow me.”).

“This kid is just one of a kind. He’s certainly a special basketball player,” Duke coach Mike Krzyzewski said. “But as a youngster, he has a maturity, it’s uncommon.”

Said Williamson, “I didn’t picture how things would happen for me. I kind of pictured how things would happen for the team. I think the season has exceeded my expectations.”

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