Safina, seeded second, had little trouble dispatching Romanian Sorana Cirstea 6-2, 6-1. Dementieva, the third seed who won at Auckland last week, eliminated fellow Russian Ekaterina Makarova 7-5, 6-1 on the hard courts at Sydney International Tennis Centre.

Safina, who was last year's French Open and Olympic runner-up, meets fellow Russian Vera Dushevina next. Dementieva, who won the gold medal in Beijing last year and is coming off a win at the ASB Classic, faces Slovakian wild card Jarmila Gajdosova.

In other action, France's Alize Cornet upset seventh-seeded Russian Nadia Petrova 6-2, 6-4. Eighth-seeded Dane Caroline Wozniacki avoided a similar fate by beating Slovakian Dominika Cibulkova 6-1, 6-2.

Also on Monday, Russian Alisa Kleybanova defeated compatriot Maria Kirilenko 6-2, 6-2, while Slovakian Daniela Hantuchova downed Czech qualifier Klara Zakopalova 6-3, 6-0. Italian Karin Knapp, who replaced Victoria Azarenka, who pulled out with an illness, lost to Gajdosova 6-4, 6-2.

The winner of the $600,000 event will pocket $98,500.