A portrait of George Dyer by Francis Bacon is to lead Christie's Post War and Contemporary Art Evening Auction in London on February 13.
Painted in 1966, the work depicts Bacon's lover and muse, who is regarded as one of his foremost creative influences. It is expected to sell for around £30m ($49.2m).
Francis Outred, head of post-war and contemporary art at Christie's Europe, commented: "Francis Bacon's position at the forefront of 20th century painting was highlighted at Christie's in November when his triptych of Lucian Freud sold for $142 million and became the most valuable work of art sold at auction.
"For the triptych we had 6 collectors who bid at over $100 million, showing both the global demand which we see in today's art market as well as the huge appeal of the artist.
"It is exciting to be able to follow this success by offering this tour-de-force portrait of George Dyer which presents a powerful portrait of arguably one of Bacon's greatest loves, painted in 1966, and one of the last full-size portraits of him to remain in private hands."
Outred went on to say that the painting was exhibited at Bacon's retrospective at the Grand Palais in Paris following his death in 1992 - lending it an added emotional resonance.
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