The archive of celebrated baseball photographer Charles Conlon auctions on August 27.
Some 7,462 original negatives are up for grabs as a single lot that has a $1m estimate and a $260,000 current bid.
Conlon (1868-1945) was among the foremost photographers of America's Game during the first half of the 20th century - his work appearing in a variety of formats.
Heritage Auctions, the company facilitating the sale, comments: "From imagery populating early Reach and Spalding guides to syndicated newspaper photography to iconic trading cards spanning the days of tobacco to bubble gum, the work of Conlon permeates the historical paper trail of the most glorious decades of baseball, almost always uncredited, the life's work of a man both anonymous and intimately familiar."
Many of the games' greatest players appear within the archive, including Ruth, Cobb, Gehrig and "Shoeless Joe" Jackson.
Heritage Auctions believes these photos should be viewed as art.
"Conlon's photography is not simple, bloodless documentation," says the auctioneer.
"We risk no hyperbole by filing his work under the heading of fine art, his deft eye and technological skill conspiring to create imagery that would strike no discordant note on a gallery wall beside Ansel Adams or Henri Cartier-Bresson."
The online sports auction also features the only verified example of a Jackie Robinson bat from his 1947 rookie season. It's valued at $300,000 and has a current bid of $150,000.
A 1904 Christy Mathewson game worn Giants jersey has reached $120,000.
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