Kitzbuehel - Lukas Rosol has advanced to his fourth quarter-final of the month by beating Andreas Haider-Maurer of Austria 6-3, 7-6 (4) at the Bet-at-Home Cup on Wednesday.
The third-seeded Czech, who also reached the last eight in Stuttgart, Hamburg and Umag, had nine aces.
He dropped serve once after double-faulting three times in a row at 1-1 in the second set but broke Haider-Maurer again when the Austrian served for the set at 5-4.
Rosol will next play Maximo Gonzalez of Argentina, who beat Albert Ramos-Vinolas of Spain 6-4, 6-4.
Rain had delayed play for four hours and started again after the matches were completed, forcing organizers to postpone the remaining six second-round ties.
Results from the third day of the ATP Kitzbuehel Cup on Wednesday (x denotes seeded player):
Lukas Rosol (CZE x3) bt Andreas Haider-Maurer (AUT) 6-3, 7-6 (7/4)
Maximo Gonzalez (ARG) bt Albert Ramos (ESP) 6-4, 6-4