Frankie Dettori steered Sandiva to a cosy victory in the Prix du Calvados at Deauville for his new boss owner Sheikh Joaan Al Thani.
The Italian celebrated with his trademark flying dismount in the winner's enclosure following this Group Three juvenile success over seven furlongs.
Trained by Richard Fahey, Sandiva held a handy position on the outside before taking the lead over a furlong out and bounding clear to beat Straight Thinking, who stayed on well for second, by a length and a half.
There was drama just after the gates opened when Sandiva's main market rival Lacarolina jumped out awkwardly in the next stall and unseated her rider Gregory Benoist.
Fahey said: "Frankie felt everything went wrong there with the loose horse, and she stuck out from the others, but she's got plenty of speed. I know the second was well fancied and I was worried about her. She's a nice filly, too.
"I'll speak to connections and I know they are keen to run her in the mile fillies' race on Arc day (Prix Marcel Boussac)."
Sandiva, who lost her unbeaten record when second to Kiyoshi in the Albany Stakes at Royal Ascot, was cut to 14-1 from 20s by BetVictor for next season's 1000 Guineas in the aftermath of the race.
