Three-time former champion Philipp Kohlschreiber has reached the quarter-finals of the Munich Open following a 6-2 6-2 win over Mischa Zverev.
Kohlschreiber next faces second seed Roberto Bautista Agut, who defeated Norwegian wildcard Casper Ruud 6-4 6-3 in the clay-court tournament on Thursday.
Third seed Diego Schwartzman lost 6-4 6-2 to Maximilian Marterer.
The German will next meet Marton Fucsovics of Hungary, who defeated Italy's Marco Cecchinato 7-6 (5) 6-1.
Defending champion Alexander Zverev plays Jan-Lennard Struff on Friday, with fourth seed Chung Hyeon facing 2014 winner Martin Klizan in the other quarter-final.