The prestigious mile-and-a-half prize on October 6 is one of three potential Group One targets under consideration for the Mitsuru Hashida-trained five-year-old - along with the Qipco Champions Fillies and Mares Stakes and the Qipco Champion Stakes at Ascot later in the month.
After springing a surprise in the Nassau Stakes at Goodwood on her penultimate start, and just a second in Britain following her highly successful career in Japan and internationally, the daughter of Harbinger followed up with a staying-on fourth in the Irish Champion Stakes at Leopardstown on Saturday.
Assistant trainer Yoshitake Hashida said: "I believe she has the two options of going to Ascot, which I believe would be more likely for the Champion Stakes, or the Arc. She will return to Newmarket tomorrow - then we will see. We might go have a look at the track at Longchamp at the weekend, before potentially running her in the Arc. She needs supplementing for the Arc, so it is a big decision for the owner. "
Reflecting on Deirdre's latest performance, Hashida believes the result in Ireland might have been different had she been granted a clear run.
He added: "She had a bit of bad luck in the race, but the horse is very genuine. We appreciate having a great mare. I think the most frustrated person was (jockey) Oisin Murphy."
Deirdre has not raced over a mile and a half since finishing fourth in the 2017 Japanese Oaks, but the step back up in trip is not expected to be an issue should the Arc plan materialise.
Hashida added: "Since she has got used to a mile and a quarter, we might keep to a mile and a quarter. I think if the owner decides to go back up to a mile and a half for the Arc, though, that she will cover it."
