Wanna add the "Holy Grail" of Pokemon cards to your childhood collection?
Hope you've got the cash ... TMZ Sports has learned a SUPER rare "Trainer" card is hitting the auction block -- but it could fetch over $100,000!!!
We're told the "No. 1 Trainer" promo card is one of the rarest pieces in the history of Pokemon ... with only seven known in existence.
According to the guys over at Heritage Auctions ... the card was handed out to winners of regional Pokemon tournaments as a sort of entry ticket into an exclusive tourney in Tokyo in 1999.