Duke superstar Jahlil Okafor is the greatest player to EVER come out of Chicago ... better than D-Wade, D-Rose, Kevin Garnett and Isiah Thomas ... so says J.O.'s father, Chukwudi Okafor.
Those others are no chumps -- some of the greatest players in the history of basketball ... but Chukwudi tells TMZ Sports his son belongs at the TOP of the list of Chi-town's finest.
"My son's absolutely the most decorated player ever from the city."
J. Okafor -- who's only 19 -- is already an NCAA Champion, 1st team All-American, 3x FIBA Gold Medalist, and has been the MVP of almost every game he's ever played.
"Not many people can say that," Chukwudi tells us, "actually, not one other person can say that."
A few bonus thoughts from Chukwudi Okafor:
On his son's college legacy: "He should go down as a legend at Duke. He brought them a banner."
On which NBA team should draft his son: "We really have no control over where he ends up, but I'll say this, I love New York and L.A."