Kieren Fallon and Frankie Dettori have both given up their rides at Warwick today.
Fallon's agent Dave Pollington explained: "Kieren has got a sore throat. It's nothing serious - he just felt a bit under the weather - and he hopes to be back tomorrow."
Andrew Stringer, who acts for Dettori, said: "Frankie's just got a little 'flu. He didn't feel too good so he decided to take the day off. Hopefully he'll be fit and well to ride at Nottingham tomorrow."
Meanwhile heavy rain has put tomorrow's Flat meeting at Nottingham in jeopardy.
Clerk of the course Charlie Moore said: "We will have a precautionary inspection at 7.00am.
"We have had an inch of rain in the past 28 hours and it keeps raining.
"The forecast is for more rain up to tomorrow morning and it is a question of when it stops.
"We could race at the moment but there is the danger we could be left with standing water."
Exeter will hold a precautionary inspection in the morning to determine whether tomorrow's meeting can go ahead following recent heavy rainfall.
"We will hold an inspection at 7.30am," a course spokeswoman said today.
"We've had lots of rain - two inches since 4.00pm on Sunday."
The going is currently described as soft.
