He established himself as must-watch-TV with fans all over the world tuning into college basketball to see him in action.
The 18-year-old was unable to lead Duke to a national title at the NCAA tournament, but his overall performance in March Madness was still blockbuster.
With the NBA draft lottery just around the corner, NBA teams have been waiting with bated breath for Williamson to declare for the draft.
He refused to do it straight after Duke were eliminated from the NCAA tournament.
But Williamson has finally made his decision public, with a post on Instagram where he paid tribute to his time at Duke as well as the help his mother has provided him over the years.
“I just want to say thank you,” he said.
“Thank you for making this season a dream for me.
“I want to thank god, Coach K, the assistant coaches at Duke, my family and all my team-mates at Duke.
“Thank you for making this year the best year of my life.
“I don’t think I can put it into words how special this year was.
“The brotherhood – it’s incredible… everything about this team was special and learning from Coach K was special.
“He taught me so much about the game of basketball in one year that made me sit back and think, ‘wow, I don’t know anything’.
“I want to thank my mum. My mum has been there since day one, without her I wouldn’t be in this situation.
“Growing up as a kid in South Carolina, I never thought I’d have the opportunity to play in Duke and for Coach K, let alone getting a chance of getting drafted.
“So I will pursue my next dream and declare for the 2019 NBA Draft.
“Thank you Duke. This has been the best year of my life.”