Patrick Mahomes Baseball Signed In H.S. Hits Auction, Expected To Fetch Five Figures

A baseball that's roughly a decade old is about to sell for thousands of dollars ... and it's all 'cause Patrick Mahomes put his "John Hancock" on it way back when he was a high school senior!!

The ball was just discovered at a thrift store in Rockwall, Texas last month ... and it's super cool. It features signatures from some of the players who took the diamond in Texas for the Whitehouse H.S. Wildcats during the 2013-14 season.

In total, there are six names scribbled on it ... but, of course, none is bigger than Mahomes -- who put a "#5" next to his autograph when he inscribed the sweet spot.

Leland's just put the piece on its auction block -- and while bidding has started at $2,500 ... TMZ Sports is told it could fetch $10,000 and up!!

While it might sound a little crazy -- considering Mahomes, after all, does play football ... it's actually not the first Mahomes-autographed H.S. baseball that's sold for a wad of cash.

Back in 2020, one that the Chiefs star and the rest of his Whitehouse teammates signed in 2013 netted its seller a whopping $6,510.

Seems like a ton of cash ... but, hey, an autographed baseball signed by Michael Jordan during his high school days did go for $36,000 -- so it doesn't seem to be a bad investment by any means.