Zion Williamson 1-of-1 Rookie Card Hits Auction Block, Could Fetch $750K!!

A basketball card collector hit the JACKPOT -- pulling an ultra-rare, 1-of-1 Zion Williamson card -- and he's not wasting any time CASHIN' IN on the super valuable piece.

Here's the deal ... an Australian fan ponied up $750 to reserve 1 card from a box of 2019-20 Panini Flawless Basketball cards (a box generally runs around $7K).

The man lives thousands of miles away (and we're still in a pandemic), so an employee from Firehand Cards in Southern California pulled the card on Christmas Eve ... while the fan watched online (see video below).

Keep in mind ... the fan knew he bought a card, but had NO IDEA which one.

The card was a Zion NBA Logoman ... arguably the most sought after basketball card of the year. The card contains Williamson's signature, and patch from a game-worn jersey from his rookie season with the Pelicans.

The fan hit up Ken Goldin of Goldin Auctions, and they struck a deal to put the card on the auction block.

Goldin arranged for his nephew who lives in Cali to pick up the card from the shop ... and deliver it to PSA -- a premiere memorabilia grading service. A day later the card was graded mint condition, and is now on the auction block.

GA tells us they expect the card to bring in around $750,000 ... once the auction goes live January 11.