Christophe Soumillon will ride the favourite Tarnawa in Sunday week's Prix de l'Arc de Triomphe at Longchamp.
Dermot Weld confirmed on Tuesday that Colin Keane will be replaced by Soumillon in Europe's premier all-aged race.
It is a rare reverse in a hugely successful season for Keane who partnered Tarnawa in both her starts this year including when an unlucky runner-up to St Mark’s Basilica in the Irish Champion Stakes.
However, Soumillon, who rode the mare to win both the Prix Veremeille and the Prix de l’Opera at Longchamp last autumn, will be back on board for the Arc.
The Belgian jockey is retained rider in France to Tarnawa's owner, the Aga Khan.
“Christophe Soumillon will ride Tarnawa in the Prix de l’Arc de Triomphe. He knows the filly well and he is His Highness’ retained jockey in France,” Weld said.
Soumillon has twice won the Arc for the Aga Khan on board Dalakhani in 2003 and Zarkava in 2008.
He had been set to maintain his partnership with Tarnawa at the Breeders’ Cup last November only to test positive for Covid-19 on the eve of the meeting.
Weld turned to Keane who was in Keeneland to ride Siskin in the Mile and the Irish man produced Tarnawa to record a memorable success in the mile and a half Turf race.
It was a first Breeders' Cup victory for both Keane and Weld. The partnership was formalised at the start of this season with Keane riding extensively for Weld when not required by Ger Lyons.
It has paid off with Keane on course to break Joseph O’Brien’s 2013 record of 126 winners in a season.
However, missing out on Tarnawa in the Arc, for which she is a general 11-4 favourite, is a blow to the 27-year-old Irish jockey.
In other news, Aidan O'Brien has indicated Santa Barbara is unlikely to make the Breeders' Cup meeting in Del Mar and her stable companion Mother Earth could be rerouted as a result.
Mother Earth had originally been targeted at a valuable race in Australia but the 1,000 Guineas winner is likely to race in the United States instead.
“Unfortunately Santa Barbara has had a setback. It doesn’t look at the moment if she’s going to make the Breeders’ Cup.
“We’ve now rerouted Mother Earth. She was going to go to Australia but we’re thinking she’ll be going to America to take in some of the races at Santa Barbara could have run in,” O’Brien reported.
O'Brien will pursue a 21st victory in all in the Alan Smurfit Beresford Stakes at the Curragh on Saturday as well as an 11th success in a row in the renowned test of future classic horses.
Great champions such as Nijinksy and Sea The Stars feature on the roll of honour in the Group Two feature.
However, it is O’Brien’s outstanding record that has dominated the race in the last 25 years since first winning it with Johan Cryuff in 1996.
Successful for the last 10 years, including with High Definition in 2020, O’Brien has a handful of entries left among the 16 horses remaining in the Beresford after Tuesday’s acceptance stage.
Indications are that the Camelot colt Luxembourg, a winner at Killarney in July on his only start to date, will take his chance. He is currently a 33-1 shot in ante-post lists for next year's Epsom Derby.
Also in the Ballydoyle reckoning is Stone Age, still a maiden after three starts, but only just touched off by Atomic Jones at Leopardstown over Champions Weekend despite a bad stumble soon after the start.