Australia's gruelling summer conditions claimed three more victims on Monday when Vera Zvonareva, Victoria Azarenka and Marion Bartoli all pulled out of the Sydney International because of injury and illness.
Zvonareva, the world number seven from Russia, pulled out of her first round-match against Spain's Anabel Medina Garrigues after suffering a bout of gastroenteritis.
A mystery virus forced Azarenka of Belarus, who claimed her maiden WTA title at the Brisbane International on Saturday, to forfeit her match against Australian Jarmila Gajdosova.
Bartoli, the former Wimbledon finalist from France, quit her match against British qualifier Melanie South after just two games because of a calf injury.
Seventh-seed Nadia Petrova also made an inglorious early exit on a baking hot afternoon at Sydney's Olympic tennis centre when she lost 6-2, 6-4 to Alize Cornet of France on a mixed day for Russia's powerful army of women players.
World number three Dinara Safina hardly raised a sweat in beating Romania's Sorana Cirstea 6-2, 6-1 but Beijing Olympic champion Elena Dementieva initially struggled in the heat before beating fellow Russian Ekaterina Makarova 7-5, 6-1 two days after winning the Auckland Classic.
Dementieva said she struggled to cope with the Australian conditions after spending the last week in New Zealand and was not surprised at the high dropout rate.
"It's never easy to get used to the weather conditions here in Australia," Dementieva told a news conference.
"It's extremely hot on the courts... so you have to be very careful."
There were no major casualties in the men's draw on Monday with Russian fifth-seed Igor Andreev defeating Canada's Frank Dancevic 7-6, 6-3 and Spanish seventh seed Tommy Robredo beating Juergen Melzer of Austria 6-3, 6-4.