NEW YORK (AP) — A Yankee Stadium ticket stub signed by Lou Gehrig on July 4, 1939 — the day he retired from baseball — is going on the auction block.

This is an undated photo provided by Heritage Auctions of a Yankee Stadium ticket stub signed by Lou Gehrig on July 4, 1939, the day he retired from baseball. (AP Photo/Heritage Auctions)

Heritage Auctions says more than 60,000 tickets were sold that day and only two are known to have survived.

Of the two, only the mezzanine box ticket was signed by Gehrig. It's estimated to bring over $100,000 at the Aug. 1 sale in Cleveland.

The owner is an unidentified collector.

Gehrig retired after being diagnosed with ALS, known today as Lou Gehrig's Disease.

In his farewell speech that day, he said "I consider myself the luckiest man on the face of the Earth."

Heritage's director of sports memorabilia, Chris Ivy, says it's "the most significant baseball ticket in the world."

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