A Ty Cobb baseball card more than ONE HUNDRED years old just sold for -- are you sitting down??? -- a whopping $504k!!! ... TMZ Sports has learned.
The card is Ty Cobb's 1915 Cracker Jack card ... and it's one of only three of its kind to ever receive a Mint 9 rating from PSA ... which is just one step below the perfect Gem Mint 10.
If you think coughing up half a milli for a baseball card is insane, just remember the Honus Wagner card holds the record for the most expensive baseball card at $3.12 million!!!
The Cobb card -- sold via Heritage Auctions -- fetched $504k, which is around $70k more than when another was sold back in 2017.
No word on who bought the prized item ... but here's a clue -- they're RICH!!!