They cost as much as football players but are likely to be a far wiser investment. In the week that saw two record-breaking sales of paintings by Lucian Freud and Francis Bacon, a new collector has been revealed. Roman Abramovich, the Russian tycoon and owner of Chelsea football club, is the mystery buyer of the two paintings, according to reliable sources.

While Abramovich is better known for studying the sometimes patchy form of the players he buys, experts say that the $120m (£61.4m) buying spree suggests that he has found a new enthusiasm. His inspiration is likely to be his model girlfriend Daria “Dasha” Zhukova, who has recently spoken of her desire to open a contemporary art gallery in Moscow.

On Tuesday at a sale at New York’s Rockefeller Center, Christie’s sold Freud’s Benefits Supervisor Sleeping, a picture of Sue Tilley stretched naked across a sofa. It fetched $33.6m, the world auction record for a living artist.

“This picture is a simple and seemingly uncomposed depiction of one of the key features of Freud’s art,” said a Christie’s spokesman. “The forceful and undeniable physical presence of people and things.”

According to The Art Newspaper, the secret buyer was again bidding at Sotheby’s sale on Wednesday evening. This time he spent $86.3m on a three-panel work by Bacon, entitled Triptych. The purchase sent a record for a painting by the artist.

As the art world celebrated the buoyant auctions despite the slump in the world’s financial markets, speculation grew over who had been the purchaser of the Freud and Bacon paintings.

Cristina Ruiz, editor of The Art Newspaper, said: “Abramovich is now said to be the buyer of both of these paintings and I’m very impressed by his choices. He has gone at the highest level, but these are good purchases and I think they will retain their price.

“Abramovich appears to be completely new to the market. It’s very interesting because the power in the art world is shifting from European and American collectors who are selling to Russian and Middle Eastern collectors. It means the market is very resilient.”

Abramovich, worth an estimated £11.7 billion in The Sunday Times Rich List this year, announced his split from Irina, his second wife, last year.

He is now in a relationship with Zhukova, the 25-year-old daughter of a former cinema projectionist who then made his fortune as an oil trader.

Zhukova has launched her own fashion label while studying homeopathy in London. Despite her reputation as a socialite, she is said to prefer a quiet night at home and is an art enthusiast.

One of her projects, to transform a 1920s bus garage in Moscow into a gallery for contemporary art and culture, is expected to be launched next month. Amy Winehouse is reported to have been offered about £1m to sing at the event.

Asked about the purchases, a spokesman for Abramovich said: “We do not comment on personal matters.”

Additional reporting: Georgia Warren

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