Robin Haase saw off second seed Dominic Thiem 6-3 7-6 (9-7) to book his place in the quarterfinals at the Halle Open.
The Dutchman saved three set points as he held off the 23-year-old Austrian, making the last eight at the tournament for the first time.
There was a win for Alexander Zverev in an all-German match as he beat Philipp Kohlschreiber 6-3 6-4, setting up a quarterfinal against Roberto Bautista Agut.
The Spaniard had a topsy-turvy match against Dustin Brown but came through 6-4 1-6 7-6 (8-6).
Meanwhile, Frenchman Richard Gasquet lined up a showdown with Haase as he enjoyed a straightforward 6-3 6-3 victory over Bernard Tomic in under an hour.