Zion Williamson is gonna be great at Duke ... but we gotta pump the breaks on hailing him as the next LeBron -- so says Grant Hill.
We got the Duke legend at LAX a couple days after Zion committed to the Blue Devils ... and Grant was pumped on Coach K locking down yet another elite prospect.
"I hope the rims are ready in Cameron," Hill told TMZ Sports .
But Grant says that even though Zion's got the tools to be a king -- athleticism, size, explosiveness -- expecting him to become THE King is too much, especially this early (remember O.