Galileo's 5yo son Waldgeist denied Enable in her bid for an unprecedented third Gr1 Prix de l'Arc de Triomphe victory, pouncing late to score an upset victory at Longchamp on Sunday to defeat John Gosden's mare.
Both Gosden and Teddy Grimthorpe, racing manager for Enable's owner Khalid Abdullah, declined to confirm the mare's anticipated immediate retirement.
Fast-finishing 16-1 shot Waldgeist prevented Enable and Frankie Dettori from making history on a dramatic afternoon at ParisLongchamp.
The Arc is Europe's richest horse race with a purse of about $5.5 million and a first prize of $3.1 million, but its history and status as a test of speed and stamina for the best middle-distance horses over three years of age makes it an icon of the sport.
This year's race offered her the opportunity to exceed seven previous two-time winners, which included Alleged and Treve.
As with Enable, connections of Waldgeist will take their time in considering the next move.
"I'm very proud that Waldgeist managed to beat such a fantastic mare, I'm delighted".
"Frankie (Dettori) committed and went for it and with the ground testing her, it's hard to show that turn of foot and Waldgeist has outstayed her on the ground".
"(I thought he would win) when he passed Enable.
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"That said, Enable was 8-13 and therefore a very short price, so it was the doubles and trebles with Battaash and Mehdaayih we were anxious about". Prince Khalid will want to reflect on all the various possibilities, give it some good thought - and hopefully we'll come up with a good answer.
"I think ground had a lot to do with it". "How can we complain?" said Lord Grimthorpe who is also chairman of York Racecourse.
"Whether she has one more race or races next year is conjecture and speculation really".
Enable looked to have a measure of her rivals, sitting just behind a leading trio off the final bend.
"We don't love her any less".
Billesdon Brook was not quite those odds this time, but still largely unconsidered at 16-1 as she returned to the scene of her greatest triumph.
Britain and Ireland filled second and third too, courtesy of outsiders So Perfect and El Astronaute - and William Haggas' One Master capped the travelling resurgence by retaining her Prix de la Foret title with a first victory in seven attempts since that success 12 months ago.
This one-mile contest presented the daughter of Zoffany with a second chance to grab Group One glory - and while she was under pressure in the hands of Shane Foley before the home turn, she responded admirably to her rider's urgings.