Reigning champion Dominika Cibulkova was a come-from-behind opening-round winner, while sixth-seeded Russian Nadia Petrova exited the draw Tuesday at the Kremlin Cup tennis event.
The fifth-seeded Slovakian Cibulkova overcame Russian Ekaterina Makarova 2-6, 6-4, 6-2 on the indoor hardcourts at Olympic Stadium.
Cibulkova beat Estonian Kaia Kanepi in last year's Moscow finale.
Romanian Simona Halep came back to dismiss Petrova 3-6, 7-5, 7-5 in 3 hours, 8 minutes on Day 2. The Muscovite Petrova was a Moscow runner-up back in 2006.
Meanwhile, Bulgarian Tsvetana Pironkova doused American Varvara Lepchenko 6-0, 7-6 (7-3) and Kazakhstan's Yaroslava Shvedova drove out Russia's Anastasia Pavlyuchenkova 6-2, 6-2.
Other Tuesday winners were France's Alize Cornet and Serbian qualifier Vesna Dolonc.
In some second-round action on Wednesday, second-seeded French star Marion Bartoli will face Swede Sofia Arvidsson, third-seeded former world No. 1 Caroline Wozniacki of Denmark will battle Poland's Urszula Radwanska and Cibulkova will face Pironkova.
An opening-round affair on Day 3 will pit seventh-seeded Russian favorite Maria Kirilenko against fellow countrywoman Elena Vesnina. Kirilenko was a Moscow runner-up two years ago.
The 2012 winner of this $740,000 tournament will collect $122,000.