If LiAngelo Ball were coming out of college this year, he'd be the No. 1 overall pick ... AHEAD of Zion Williamson -- so says LaVar Ball, who tells TMZ Sports, "He can't hold a candle" to Gelo.
"He ain't no big Baller," LaVar says of the Duke superstar ... "He's a Williamson. Williamsons ain't stronger than Ballers!"
Of course, Gelo ain't available for this year's NBA Draft ... he already had his shot to be taken in 2018 -- but wasn't picked with any of the 60 selections.