Racing:Goldikova could finish only third as Varenar got up in the dying strides to spring a huge surprise in the Total Prix de la Foret at Longchamp.
The red-hot favourite looked like landing the spoils when she took over from Welsh Emperor early in the straight.
However, she had run quite keen from her wide draw under Olivier Peslier and could never pull clear of her rivals.
As Sweet Hearth came to challenge, it was Stephane Pasquier who brought the Aga Khan-owned Varenar with a strong run to complete a Group-race double for Alain de Royer-Dupre, who struck earlier with Manighar in the Prix Chaudenay.
A downcast Freddie Head said of Goldikova: "I do not know what happened. They went a gallop, but that is the name of the game. She didn't quicken. Turning into the straight she did not pick up and when he (Peslier) asked her she stayed on at the one pace.
"She might have used herself too much early on, but you couldn't say for sure. For the moment she is going to the Breeders' Cup, but nothing is definite and we will have to just see."
The winning owner's daughter Princess Zahra said: "He doesn't really show that much in his work so that was lovely and I think we've found our distance (seven furlongs).
"He's a fast horse and he's from a fantastic family."
Christophe Soumillon was sixth on Oiseau de Feu on his opening ride back after he fractured his elbow last month but was first past the post in his second when he rode Tamazirte to victory in the Qatar Prix Daniel Wildenstein.
He hit the front well inside the final furlong to deny Danse Grecque with Murcielago third.
Soumillon said: “I knew she was a good filly. You can forget her last race as she was runner-up in the Guineas and the Oaks and she was favourite today.
“I feel great and rode my retired horse in Les Lions in Chantilly eight days ago. I was with my wife and my father and the horse gave me a good feeling so I knew I was ready to come back.
“Riding five or six for His Highness (the Aga Khan) this weekend would have been too much but then this opportunity came around.
“I sent Jean-Claude (Rouget) an SMS yesterday to say that if he couldn’t get a jockey then I would ride for him.
“He rang me back laughing thinking that I was joking, but I wasn’t joking and wanted to give this opportunity my everything.
“It is unfortunate what happened to Christophe but it happened to me a few weeks ago.
“I had to go to Deauville to pass the doctor, and I had to drive quickly to get there and back to Paris.”