Frankie Dettori looks set to play a major part in whether Fantasia runs in the stanjames.com 1000 Guineas after her electric display in the Leslie Harrison Memorial Nell Gwyn Stakes at Newmarket.
American owner George Strawbridge is keen for the Italian to maintain the partnership, and the jockey's commitments to Godolphin in the fillies' Classic could see Fantasia diverted to the French equivalent.
Strawbridge already had the ante-post favourite for the Guineas in the shape of Rainbow View, but she was joined towards the head of the market by Fantasia after she scooted clear in the spring sunshine to stamp her class on the trial.
Should she be committed to the Newmarket event on May 3, Ladbrokes quote her and Rainbow View as the 2-1 joint-favourites, while the sponsors have the latter as the 6-4 market leader and Fantasia at 5-2. Sky Bet go 7-4 with a run.
The pair were separated by two and a half lengths in the Fillies' Mile last autumn, and both made their seasonal bows on the Rowley Mile on the same spring afternoon, although in different circumstances.
John Gosden treated the unbeaten Rainbow View to a racecourse gallop at lunchtime, while three hours later Fantasia faced 10 rivals in the seven-furlong event.
Luca Cumani's daughter of Sadler's Wells glided into contention and forged clear with serious determination for an impressive seven-length success.
Strawbridge, who bought Fantasia during the winter, had been keen to send the winner to Longchamp for the French Guineas on May 10 - but is hanging fire on a definite decision, partly owing to the availability of Dettori.
The Pennsylvania-based head of Campbells Soup Company, said: "I am just thrilled Fantasia is so good and has trained on.
"I wouldn't rule out both fillies running in the English Guineas as there are many days left before the race.
"I am very lucky to have two such good fillies. I am heading back to the States tonight and will let some days go by and see what happens.
"I just want to enjoy this win as Fantasia is a very special filly.
"Rainbow View is a bit more nerve-wracking to watch. They are both entered in the English Guineas and I need to discuss plans with Luca - it is silly to dismiss anything.
"There are various factors to be weighed up, and one of the main ones would be if we can get Frankie, as he suits this horse very well."
Dettori, however, virtually ruled himself out of the reckoning for the British Guineas owing to his Godolphin commitments.
He said: "Breathtaking, wasn't it?
"We always knew she was good and has wintered well.
"If she does come back to Newmarket I won't be able to ride her as I have a horse to ride for Godolphin."
In the last 10 years, only Speciosa in 2006 has progressed from the Nell Gwyn to land the Guineas.
It was put to Cumani that we haven't seen such an impressive winner of the Nell Gwyn in a few years, and he quipped: "The winners of the Nell Gwyn don't have a good record in the Guineas, which is why we are going to France!
"Joking aside it is up to the owner and I am happy to go wherever he sends me."
He continued: "I didn't expect her to win like that, but I am a sort of pessimist so I was happy to see her go clear, for two reasons.
"Firstly because George has shown a lot of faith in the filly through the winter and I didn't want to let him down.
"And secondly because I hold this filly in the highest esteem and one hopes not to be wrong.
"I thought she was going to win but I didn't expect to see her win like that.
"She will improve for the race and for going an extra furlong too."
