Ryan Moore will not return to action until next week after damaging his wrist in a fall at Windsor on Monday evening.
The earliest the champion jockey will be back race-riding will be Monday, a day before the start of one of the biggest meetings of the year, the four-day York Ebor Festival.
He suffered the wrist injury when his mount, Rocket Rob, fell after having passed the winning line in third place in the rippleffect.com Handicap.
"I've taken him off until the end of the week to give him a little bit more time," said his agent Tony Hind.
"Hopefully he'll be back for York. We've got to monitor it. It's a day-by-day thing at the moment.
"He said to me he wouldn't be able to ride on Saturday and I told him not to ride on Sunday either.
"I told him to give it another day and then see how we are over the weekend. We are going to speak on Saturday after he's ridden out."
Moore, three-times champion, is currently third in this year's title race behind Paul Hanagan and Richard Hughes.
Impressive Newmarket winner Casual Glimpse has been supplemented for the Irish Thoroughbred Marketing Gimcrack Stakes at York on Wednesday. Richard Hannon's youngster is taking a big step up in class from conditions company to a Group Two but Barry Simpson, racing manager for the owner Robert Ogden, is hopeful he will be up to the task.
"I think Richard is very pleased with his progress. It is a step up for him and it's a calculated risk that we're taking, but it's a race we think could be within his capabilities," said Simpson.
"We really left it up to Richard to make the decision and there aren't really a lot of other opportunities for him.
"We took on board what Ryan Moore said after riding him at Newmarket and he felt that the horse was ready to be stepped up into much better company. One would have liked to have had an intermediate race in between perhaps but we're dealt with what we've got and what we do know is that the horse is in good shape."