Sir Bob Parker has suffered an injury that means he could be ruled out for the rest of the season, according to trainer David Menuisier.

Third in the Group Two Prix Greffulhe at Saint-Cloud last month, the Michael Watt-owned son of Siyouni was being prepared for the Derby when he met with a setback, which was more serious than first thought.

Menuisier said: “It is not extremely serious. He had a chip in the hind fetlock and that did bother him. We had to take that chip out and obviously, since he has had that operation, you have to give him a little bit of time to recover.

“I am really not sure when he will be fit to run again. I am not sure he will be seen again this season, because I am not going to push him to fit into any box. He is too nice a horse.”

Sir Bob Parker was two and three-quarter lengths behind Onesto in the Prix Greffulhe and the winner was subsequently sixth, from an unfavourable draw, in the French Derby at Chantilly on Sunday.

Menuisier added: “His form is rock solid, because when you look at the Prix du Jockey Club again, Onesto was a very unlucky horse in the race, being drawn out wide. With a better draw, he would have been in contention for a place at least.

“That will stand us in good stead. We know we are right there at the top level with the horse. We won’t change attitude. We will remain patient and things will come right.”

Royal Ascot contenders will also be thin on the ground for the Pulborough handler, after setbacks to Newbury Spring Cup runner-up Migration and decent handicapper Flyin’ Solo.

Menuisier added: “As we speak, I am not sure we will have anything going to Ascot.

“Migration is sidelined at the moment for a couple of months and unfortunately, the one I had pencilled in for the Duke of Edinburgh, Flyin’ Solo, is also sidelined until later in the summer. You may not see either until the autumn.”

Goodwood’s Cocked Hat winner Lionel is still on course for the Dubai Duty Free Irish Derby at the Curragh on June 25, however.

Menuisier confirmed: “That is the plan – the Irish Derby. He is in good form and I am happy with him.”