Reigning champion Dominika Cibulkova came back from a set down Tuesday to defeat Ekaterina Makarova in the Kremlin Cup first round.
The Slovak, seeded fifth for this year's event, recovered from a first-set lapse to win 2-6, 6-4, 6-2 and set up a second-round match with Bulgaria's Tvsetana Pironkova.
"It's not the best surface, I would say, and it was not easy to get into the rhythm, so that's why I had many mishits in the first set," Cibulkova said.
"Then I got into the rhythm. I was making more shots, running better."
Cibulkova beat Kaia Kanepi of Finland to win last year's event.
The 20th-ranked Makarova has got past the first round only once in six attempts at her home tournament.
Earlier, Pironkova pulled off a surprise 6-0, 7-6 win against illness-hit U.S. No. 2 Varvara Lepchenko.
Pironkova is ranked 23 places below Lepchenko at No. 44.