Elena Rybakina won both of her opening two matches at the French Open in straight setsDates: 28 May-11 June Venue: Roland Garros, ParisCoverage: Live text and radio commentaries of selected matches across BBC Radio 5 Sports Extra, the BBC Sport website and appWimbledon champion Elena Rybakina pulled out of the French Open shortly before her third-round match because of illness.
One of the favourites for the title at Roland Garros, the 23-year-old Kazakh was set to play Spain's Sara Sorribes Tormo at 10:45 BST on Saturday.
"I was not sleeping well two days. I had fever, headache," she said.
"It's difficult to perform, to run and even breathe. So I think that was the only right decision I could make."
Rybakina, seeded fourth, was seen as a main contender for the clay-court Grand Slam, having won the recent Italian Open and breezed through her opening two matches without dropping a set.
Rybakina is part of the emerging 'big three' on the WTA Tour, alongside Polish world number one Iga Swiatek and Belarusian world number two Aryna Sabalenka, with the trio having won the past four Grand Slam titles between them.
They are the leading players on the WTA Tour this season, although Rybakina is still fourth in the 52-week rankings - behind American Jessica Pegula - after not receiving points for winning Wimbledon last year.
Two-time French Open champion Swiatek plays her third-round match in Paris later on Saturday, while Australian Open champion Sabalenka is already through to the last 16.
"Of course I'm really upset not be able to play, but I guess that's life. There is a lot of ups and downs," said Rybakina.
"I wanted to give 100%, and obviously I'm far from being 100%.
"I was already not feeling good yesterday and the day before, so I didn't sleep two nights and had some fever.
"I really tried on the warm-up, but I feel that the right decision is to withdraw, because it's really tough to play with these conditions."
Sorribes Tormo, ranked 126th in the world after injury problems last year, moves into the fourth round and will take on Russian 23rd seed Ekaterina Alexandrova or Brazilian 14th seed Beatriz Haddad Maia.
