David Goffin survived an almighty scare at the Swiss Open Gstaad on Wednesday as he battled back from a set down to beat Radu Albot.
Top seed Goffin had been expected to ease past the world number 132 but quickly found himself a set down against the Moldovan.
Eventually the Belgian found some rhythm and after wasting two set points he levelled thanks to a tie-break, and he needed another nervy breaker - in which he saved four match points - to progress to the quarter-finals 2-6 7-6 (9-7) 7-6 (9-7).
The other seeds in Switzerland had fewer problems as Roberto Bautista Agut, Robin Haase and Paolo Lorenzi all won in straight sets - the latter in the first round.
Day five at the ATP 250 event also saw Ernests Gulbis and Henri Laaksonen reach round two, while Denis Istomin is into the last eight after beating Dustin Brown 6-3 6-1.
The German Tennis Championships in Hamburg saw its top two seeds depart on Tuesday but David Ferrer ensured he did not suffer the same fate with a first-round win over Nikoloz Basilashvili.
He will meet Federico Delbonis in round two and could come up against Aljaz Bedene in the last eight after the Briton eased past lucky loser Jose Hernandez-Fernandez in straight sets.
Seventh seed Fernando Verdasco was another early casualty, though, as Jiri Vesely bounced back from losing a second-set tie-break 7-0 to secure victory.
Meanwhile, Florian Mayer and Diego Schwartzman are the first two players in the quarter-finals after triumphs over Andrey Kuznetsov and Cedrik-Marcel Stebe respectively.