Diamond Necklace suffered the first defeat of her career as the Christophe Ferland-trained Aventure bounced back to her best in the Sumbe Prix Jean et Louis Romanet.
A first win in the Group One looked in the grasp of the master trainer with the 1-5 favourite, but she failed to pick up as well as the winner who quickened well clear under Maxime Guyon.
The five-year-old was only fourth behind Calandagan in the Grand Prix de Saint-Cloud last month, but seemed to relish the testing ground and drop in trip here.
Diamond Necklace's six previous wins included the Prix Marcel Boussac, Poule d'Essai des Pouliches, Prix de Diane and Nassau Stakes, but the mount of Ryan Moore had no obvious excuses here having had a prime position when the race developed turning for home.
In the end, she only just held off the Charlie Johnston-trained Timeforshowcasing for second who produced a fine effort having been fairly prominent throughout behind the pace-setting Moments Of Joy.
Johnston said: "We are absolutely over the moon, she's danced plenty of dances, been well travelled.
"I thought we were biting off more than we could do againstthe best fillies in Europe – she's stepped up to a new level.
"The testing ground is important to her - she might get more respect that she's a top-class filly in her own right."
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