The red-hot run of trainer Jean-Claude Rouget and jockey Christophe Lemaire continued as Stacelita absolutely bolted up in the Prix de Diane (French Oaks) at Chantilly.

Settled in second behind the pace-setting Onega Lake, Lemaire had an armchair ride all the way and his mount's acceleration was stunning when he pressed the button just inside the two pole.

Stablemate and French 1000 Guineas runner-up Tamazirte made it another big-race one-two for Rouget, but British hope Fantasia finished well held.

The daughter of Monsun had destroyed a Group One field by six lengths previously in the Prix Saint-Alary at Longchamp on soft ground, and proved conclusively here that she handles quicker conditions just as well.

Bookmaker reaction was swift with William Hill going 7-1 for the Prix de l'Arc de Triomphe about the winner, who looks like she could be the new Zarkava and was taking her unbeaten record to five. Victor Chandler cut her to 8-1 from 16s.

Coral also go 7-1, making her second-favourite for the Arc behind Epsom Derby hero Sea The Stars. Spokesman David Stevens said: "Zarkava proved to be too good for the colts in last year's Arc, and after winning the French Oaks in similar style, Stacelita has to be considered a credible contender to emulate that great filly at Longchamp in October."

Having won the French 1000 Guineas with Elusive Wave and the French Derby with Le Havre, Rouget has rightly emerged as a superstar across the Channel, and is set to saddle the former as well as Never On Sunday at Royal Ascot.

Rouget said: "This is enormous for me. If you had asked me in February I would have said this could never happen.

"I am never good before a race. I was worried about the ground for Stacelita and worried about the trip for Tamazirte, but Stacelita has gone on the ground and the other filly has stayed the distance so it has worked out well.

"I would think that Stacelita will go for the Prix Vermeille and then the Arc - that would be a good programme for her."

Fantasia's trainer Luca Cumani said: "The winner looked phenomenal but our filly did not fire and did not pick up when asked after travelling well through the race.

"Her preparation could not have been better but perhaps she does not like to travel. She had a bad journey over, was upset yesterday and is perhaps still immature.

"We will have to go home now and regroup."