Russia's Anastasia Pavlyuchenkova made a winning start at the St Petersburg Ladies Trophy with a three-set victory over in-form qualifier Klara Koukalova.
Pavlyuchenkova, the fifth seed and world number 28, triumphed 6-4 4-6 6-4 over the Czech in just over two hours to reach the second round.
She will next face German Carina Witthoeft, who saw off another qualifier in Tamira Paszek 6-3 6-3.
There was further Russian success as Margarita Gasparyan beat Bojana Jovanovski 6-1 6-2.
The four top-seeded players - Belinda Bencic, Roberta Vinci, Caroline Wozniaki and Ana Ivanovic - are already through to round two courtesy of byes.
Source: PA
