A set of history-changing documents went up for sale this week with the 2016 Major League season kicking off.

The 1857 documents titled "Laws of Base Ball" establish the essentials of the modern game: The distance of the base paths is 90 feet, the length of the game is nine innings and nine players are in the field.

They do so three years earlier than the 1860 birth date currently recognized.

The authenticity and significance of the documents are verified by experts that include John Thorn, Major League Baseball's official historian.

The documents were authored by Daniel Lucius "Doc" Adams, making him the founding father of America's pastime, not Alexander Cartwright, who now is credited.

"He's the true father of baseball and you've never heard of him," Thorn, a consultant on the sale of the papers, told The Associated Press in a phone interview.