Boxer, a sculpture by African American artist William Edmonson (1874-1951) will lead an auction of outsider art at Christie's.
The Liberation through Expression sale will take place in New York on January 22, with Edmonson's work valued at $150,000-250,000.
Boxer is believed to have been inspired by champion fighter Joe Louis
Edmonson was a self-taught stonemason, who began his career carving tombstones.
His simple but powerful sculptures caught the attention of the art world and in 1938 he became the first African American to have a solo exhibition at New York's Museum of Modern Art.
Christie's explains: "Boxer is an incredibly sophisticated object. Likely modeled after Joe Louis, it is one of the most important sculptures created in interwar America�Ǫ
"One of only two pugilists carved by the artist, Boxer is a reflection of American popular culture of the era and shows Edmondson's pride in his cultural identity.
"Kept on a shelf protected by an overhang in Edmondson's Nashville, Tennessee yard, Boxer was by many accounts one of the artist's favorite works."
The record for Edmonson's work is $263,000 - set for Mother and Child at Christie's in 2014.
An untitled work by Martin Ramirez is valued at $60,000-100,000.
Ramirez was born in Mexico and travelled to the US to find work in 1925. In 1931 he was diagnosed with schizophrenia and spent the next 30 years in various institutions.
One of his doctors noticed his extraordinary artistic talent and provided him with materials. His work was shown in galleries across the US, at first anonymously.
In 1973, long after his death, it was shown for the first time under his own name.
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