Francis Bacon's "Second Version of Study for a Bullfight" No. 1 (1969) brought an over-the-estimate hammer price of $41 million at Sotheby's last night and a Self-Portrait, painted when he was 60, sold for a strong $29.5 million (plus commission).

Two works by Francis Bacon took more than $70 million (£35 million) at auction today in New York.

The paintings, Study For Bullfight No 1, 2nd Version, and Self Portrait, have been in a private European collection for decades.

Last week, shares of Sotheby’s plummeted after a Vincent van Gogh painting drew no bids at an impressionist art auction, prompting speculation that fallout from credit-market losses has hit the art world.

But today’s auction follows the sale of Bacon’s Study From Innocent X for ($52.6 million) £26.6 million in New York in May this year, which established a world record price for the artist at auction.

Tobias Meyer, Sotheby’s worldwide head of contemporary art, said: “Study for Bullfight No 1 is an extraordinary painting symbolising Bacon wrestling with artistic desire.

“Here, he is battling the demons that occupy his violent subconscious, and in Self Portrait he struggles with these same issues of identity.

“Both masterpieces explore the same conflicts but with different outcomes.”

Executed in 1969, Study for Bullfight No 1, 2nd Version, comes from a series of three paintings depicting the subject.

The present canvas sold for $41 million (£20.5m).

From the same year, Self Portrait, painted when Bacon was 60, sold for $29.5 million (£15m).

Both works will be on public exhibition in Madrid from Friday before going on exhibition in New York later this autumn.

Bacon (1909-1992) was born in Dublin to English parents and moved to London in 1926.

Although he had no formal training as an artist, he started to exhibit his work in the 1930s.

A decade later he became well known, causing sensation among the artistic community with his angst-ridden paintings of twisted and mutated forms.

Bacon would become one of the most prominent contemporary artists of his lifetime, with major retrospectives in Paris in 1971, the Metropolitan Museum in New York in 1975 and the Tate in London in 1985.

Bacon died of a heart attack in Madrid in 1992. Today, his work is among the most popular of 20th Century art at auction.

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