Hayley Turner has been forced to give up her rides at Kempton on Wednesday evening after suffering a minor injury at Lingfield.
Britain's top female rider rode in two races at the Surrey venue but did not go on to the Sunbury venue where she had four mounts booked after being signed off by the doctor.
"I believe she got a whack in the eye and the doctor has signed her off," said her agent Guy Jewell.
"She's been riding at Lingfield this afternoon and the doctor has signed her off unwell. I think she'll be back tomorrow."