Following are the results from the fourth day of the ATP St. Petersburg Open Thursday.
Second round:
6-Ernests Gulbis, Latvia, bt Jurgen Zopp, Estonia, 6-3, 1-6, 6-3
Michal Przysiezny, Poland, bt 1-Fabio Fognini, Italy, 6-3, 5-3 - retired
7-Lukas Rosol, Czech Republic, bt Karen Khachanov, Russia, 6-4, 6-4
Joao Sousa, Portugal, bt Sergiy Stakhovsky, Ukraine, 3-6, 6-4, 6-0
4-Dmitry Tursunov, Russia, bt Konstantin Kravchuk, Russia, 6-3, 6-0