Istomin through to round two
Denis Istomin fought back from a second down to book his place in the second round of the Kremlin Cup with a 5-7 7-5 6-1 win over Bjorn Pau.
Eighth seed Tatsuma Ito of Japan also dropped a set before safely advancing, as he took one hour and 44 minutes to see off Roberto Bautista-Agut of Spain 6-3 1-6 6-2.
Also in men's action, Lukas Rosol of the Czech Republic beat another Spaniard, Daniel Gimeno-Traver, 7-6 (11/9) 7-6 (6/2), and Malek Jaziri of Turkey overcame America's Rajeev Ram 6-3 6-1.
In the women's event, Czech eighth seed Lucie Safarova beat wild card Margarita Gasparyan 6-3 4-6 6-2, while there were also wins for Klara Zakopalova, Urszula Radwanska and Sofia Arvidsson.