Bidding on Babe Ruth's original 1918 contract for the Boston Red Sox is at $370,000 in a sale dedicated to the legendary batter at Goldin Auctions in New Jersey on July 12.
Ruth began playing for the Red Sox in 1914, where he built a phenomenal reputation as a pitcher and later as a batter.
His showmanship and penchant for hitting home runs led to an increase in attendance, effectively changing the way the sport was played.
Goldin states: "This contract, the Babe's own, is the only 1918 that has survived and is the earliest Babe Ruth Player's Contract known!
"The historical significance of the year 1918 to Ruth scholars is paramount - that was the year he began the transition from ace pitcher to the slugger he became known as."
The contract was Ruth's own personal copy and is one of three known examples. The Boston Red Sox and the American League hold the others.
A Louisville Slugger bat used by Ruth during the 1918-1920 seasons is at $240,000.
The bat is the only example known to have been gone with Ruth when he was sold by the Red Sox to the Yankees. It was later acquired by pioneering collector Eddie Maier and is inscribed "To My Friend Eddie Maier from Babe Ruth".
In addition to the signature, it shows ball contact marks, and cleat marks from where the Bambino knocked the mud off his boots.
Baseball memorabilia will also feature at Heritage Auctions on July 31, including a Yankees cap worn by Lou Gehrig.
Check out all our sports memorabilia here.
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