What is the only Da Vinci painting on the open market worth? A Russian billionaire believes he was swindled when he bought it for $127.5 million. This week he will find out if he was right.

"Salvator Mundi", a painting of Jesus Christ by the Renaissance polymath Leonardo da Vinci circa 1500, is the star lot in New York's November art auctions, that will see Christie's and Sotheby's chase combined art sales of more than $1bn.

It goes under the hammer at Christie's on Wednesday, something of an incongruous lot in the post-war and contemporary evening sale, which attracts the biggest spenders in the high-octane world of international, billionaire art collectors.

The auction house, which declines to comment on the controversy and identifies the seller only as a European collector, has valued it at $100 million.

"Look at the painting, it is an extraordinary work of art," said Francois de Poortere, head of the old master's department at Christie's. "That's what we should focus on."

But the price will be closely watched -- not just as one of fewer than 20 paintings by Da Vinci's hand accepted to exist, but by its owner, Dmitry Rybolovlev, the boss of football club AS Monaco who is suing Swiss art dealer Yves Bouvier in the city-state.

Rybolovlev accuses Bouvier of conning him out of hundreds of millions of dollars, in parting with an eye-watering $2.1bn on 37 masterpieces. One of those works was "Salvator Mundi" which has been exhibited at The National Gallery in London.

Bouvier bought the Da Vinci at Sotheby's for $80 million in 2013. He resold it to the Russian tycoon for $127.5 million.

The painting's rarity is difficult to overstate. For years it was presumed to have been destroyed. In 1958, it fetched 45 pounds ($60 in today's money) and disappeared again for decades, emerging only in 2005 when it was purchased from a US estate.

It was long believed to have been a copy before eventually being certified as authentic. All other known paintings by Da Vinci are held in museums or institutional collections.

"For auction specialists, this is pretty much the Holy Grail," Loic Gouzer, co-chairman of Christie's Americas post-war and contemporary art department, said. "It doesn't really get better than that."

Ferrari first

Christie's has sought to emphasize Da Vinci's inestimable contribution to art history by hanging "Salvator Mundi" next to Andy Warhol's "Sixty Last Suppers" - which depicts Da Vinci's "The Last Supper" 60 times over, also on sale with a $50 million estimate.

Pablo Picasso holds the world record for the most expensive piece of art ever sold at auction. His "The Women of Algiers (Version O)" fetched $179.4 million at Christie's in New York in 2015.

Other highlights being offered by the auction house are "Contraste de formes", a 1913 Fernand Leger valued at $65 million, and "Laboureur dans un champ" by Van Gogh, painted from the window of a French asylum in 1889 and valued at $50 million.

Sotheby's, whose May sales languished behind Christie's, says it has more than 60 works making their auction debuts this week.

Chief among them is Francis Bacon's "Three Studies of George Dyer", valued at $35-45 million, and which Sotheby's says is appearing in public for the first time in 50 years.

Painted in 1966 during his passionate relationship with Dyer, two other such triptychs are in museums and two others have been offered at auction in recent years.

Sotheby's other star lot is a 1972 Warhol "Mao", exhibited in Berlin, Turin and Paris, and now back in public view for the first time since 1974. It has been given an estimate of $30-40 million.

Each of the other 10 "Mao" paintings of the same size is in prestigious public and private collections, including the Andy Warhol Museum, Pittsburgh. Sotheby's calls it one of the most iconic images of the 20th century.

But, for the first time, the house has added a collector car to an art auction, offering Michael Schumacher's Grand Prix winning Ferrari for upwards of $4million on Thursday. Is it a work of art, though?

"No, it's not," says Gregoire Billault, senior Sotheby's vice president. "But it's... the very best racing car ever sold at an auction."