Emmitt Smith is turning into "Emmint" Smith.
The NFL's career rushing leader has minted more than $350,000 for charity by selling some of his extensive collection of game-used items.
Now Smith, who has kept every single touchdown ball from his career, is auctioning off the ball he carried in his record-breaking run.
The starting bid is $10,000, but the ball is expected to break the all-time record for a football sold at auction. That mark is already held by Smith, who sold the ball he carried to his first touchdown for $24,922.
"This will be the most expensive football ever sold," said Michael Barnes, a consultant to Smith for the selling of his collection.
Last year, Smith passed Walter Payton's mark of 16,726 career rushing yards on Oct. 27, with an 11-yard scamper in the fourth quarter against the Seattle Seahawks. Smith's current rushing record stands at 17,354 yards, but he has not played in a game since he broke his left shoulder blade seven weeks ago.
"This is just one way that I can continue to give back," Smith said in a statement. "I have always believed that I have a responsibility to make an impact beyond the football field."
Bidding will be conducted by MastroNet, an auction house that is offering the Smith ball among more than 2,000 other items in an auction that begins Dec. 1 and concludes on Dec. 19. Other items in the auction include the infamous Steve Bartman baseball and Lou Gehrig's 1936 New York Yankees contract.
Darren Rovell, who covers sports business for ESPN.com, can be reached at Darren.firstname.lastname@example.org.