Australia's [Images] gruelling summer conditions claimed three more victims on Monday when Vera Zvonareva [Images], Victoria Azarenka and Marion Bartoli all pulled out of the Sydney International because of injury and illness.

Zvonareva, the world number seven from Russia [Images], 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 [Images] finalist from France [Images], 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 [Images] 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 [Images] 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 [Images] 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 [Images] Frank Dancevic [Images] 7-6, 6-3 and Spanish seventh seed Tommy Robredo beating Juergen Melzer of Austria 6-3, 6-4.

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