Jean-Claude Rouget© Photo Healy Racing
Unbeaten dual Classic winner La Cressonniere will not run in the Prix de l'Arc de Triomphe next weekend.
The Jean-Claude Rouget-trained filly had been aimed at the Chantilly feature on the back of victories in the French 1000 Guneas and Oaks, and enjoyed a straightforward prep race at Deauville last month.
Only Roger Varian's Postponed was ahead of her in the ante-post market on Europe's middle-distance championship, but a setback has derailed her participation.
Rouget told Press Association Sport: "There is a problem, not a very strong problem but we had to do treatment and that means we cannot run her on Sunday.
"It's not very important for the future, but enough for her not to run on Sunday.
"We don't know exactly what it is. She has to go to the topography and so on to have it checked it out. The problem is towards the back.
"It has happened before with Harbinger and Danedream."
Rouget stressed plans for his star colt Almanzor, winner of the Irish Champion Stakes, would not change, and he will still be aimed at the Qipco Champion Stakes at Ascot on October 15.
He said: "Almanzor will not run. He will go to Ascot."
