Michelle Payne will not compete in the Shergar Cup team jockeys challenge at Ascot because of illness.

Hollie Doyle will replace the Melbourne Cup-winning jockey who missed the event last year because of injuries suffered in a race fall at Mildura.

"It is with great disappointment that because of a virus I have contracted since arriving in England, I find I am unable to ride in the Shergar Cup competition today," Payne said in a statement issued by Ascot officials.

"I saw the doctor yesterday and we had both hoped the medication prescribed would kick in, but unfortunately that has not been the case and I am not well enough to compete today.

"I had been looking forward to being part of this special event for a long time. Joining the girls team had been had been a major goal of mine over the last 12 months, since missing the opportunity due to injuries sustained in a fall last year.

"I would like to thank everyone for their support and encouragement and would love to return another time."

Payne was the subject of controversy when she left a media function on Friday saying she was unwell.

Nick Smith, Director of Racing & Communications at Ascot said they were grateful Doyle could step in.

"It's such a shame for Michelle that she's unable to ride today (Sunday AEST)," he said.

"We hope she will be able to participate in the event another time and in the meantime hope that the British audience get to see her next week at Newbury."

Payne will ride Melbourne-bound Kaspersky at the Newbury meeting.

Payne's brother-in-law Kerrin McEvoy will captain the Rest of the World team.