Moore was due to ride at the Curragh on Saturday but was withdrawn from all horses by midday.
Pictured: Ryan Moore poses with the Nassau Stakes trophy after guiding Whirl to success.
Ryan Moore could miss the rest of the Flat season with a stress fracture in his femur.
Moore is a jockey at Aidan O'Brien's powerful Ballydoyle racecourse, while the Coolmore stable now faces the prospect of being without one of the world's best jockeys on the horse-breeding side of the campaign as countless major races loom on the horizon.
O'Brien said: “Ryan is fine. He had a big problem with his right leg after the Irish derby.”
“They did everything they could to try and fix it but they couldn't, so yesterday he went for scans and x-rays. He has a fractured femur.
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“He had some difficulties after the Irish derby, but he is doing his best.
“When he was diagnosed with a stress fracture in his femur, that was the solution. There's only one thing that can fix that, and that's time.”
Asked if he expected to be able to ride again this season, O'Brien replied: “I'd say he'd be very lucky.”
Sourse: skysports.com
