Daniel Lucius "Doc" Adams' the Laws of Base Ball (1857) has sold for a record $3.2m at SCP Auctions.
The lot is now the world's most valuable baseball document, as well as being the third most valuable piece of sports memorabilia ever auctioned.
It lays out some of the key tenets of the game, including the distance from pitcher to batter and the settings of the bases.
It was only discovered recently, having been bought in a 1999 auction and archived. It realised $12,650 then - resulting in growth of 38.4% per annum.
Prior to that, most of the credit for the sport's development was given to Alexander Cartwright of the New York Knickerbockers Base Ball Club; who codified the Knickerbocker rules in 1860.
The paper shows that Adams, president of the club in 1857, also deserves a share of the credit. His work predates Cartwright's rules by three years.
As baseball historian John Thorn explained in the run-up to the sale: "When Doc Adams set to work in late 1856, none of these aspects of the game were settled.
"This was some seven years after Cartwright had left New York for Hawaii, never to return.
"For his role in making baseball the success it is, Doc Adams may now be counted as first among the Founding Fathers of Baseball."
The lot is the latest founding sports document to sell for a major sum at auction. James Naismith's Rules of Basketball (1891) holds the record at $4.3m.
Babe Ruth's 1920s Yankees jersey is the most valuable piece of sports memorabilia. It auctioned for $4.4m in 1920.
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