Kieren Fallon, who felt unwell after riding in the first three races at Southwell yesterday, gave up his remaining three mounts complaining of a viral infection.
Fallon, who is due to ride at Folkestone today, said: "I shall ride work in the morning and then see how I am. If I feel okay, I will go to Folkestone but if I don't feel I can do justice to my mounts, I shall give the meeting a miss."
Fallon picked up a £70 fine for not producing his medical record book, which he had left in Germany, where he was riding yesterday.