CHARLOTTE, N.C. — A Duke math professor estimates that picking the perfect NCAA Tournament bracket is about 1 in 9 trillion.

Not even the so-called experts can get it right.

So NBC Charlotte Sports Director Nick Carboni took a bracket to Hornets forward Marvin Williams, who won the NCAA Tournament in 2005 with North Carolina.

If he played in it, he knows who can win it.

Williams picked upsets like 11th-seeded Belmont over sixth-seeded Maryland, and took a 12 over 5 in Liberty over Mississippi State.

But there’s no doubt who he was picking to go all the way. In fact, the first mark he made with his Sharpie was to put North Carolina as the winner.

“I feel great about the way we're playing right now,” said Williams.

Williams has the Tar Heels defeating Tennessee in the Final Four. On the other side, he thinks Duke will lose to Gonzaga, with UNC beating Gonzaga in a rematch of the 2017 final.

Former Tar Heel Marvin Williams picks NCAA bracket

And along the way, Williams reminisced about the Tar Heels tournament run in 2005, his only season with the program.

“It meant everything,” Williams said. “I feel like playing at the University of North Carolina those moments I'll never forget. It's probably the most fun I've ever had playing basketball.”

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