Prime-seeded Iga Swiatek beat Elise Mertens 6-3, 6-4 to advance to the Porsche Grand Prix quarterfinals on Thursday.
The highest-ranked Swiatek will face subsequent Emma Raducanu, who knocked out Linda Noskova 6-0, 7-5.
Earlier, fourth-seeded Elena Rybakina battled her approach into the quarterfinals in a curler coaster 7-6 (3), 1-6, 6-4 victory over Veronika Kudermetova.
Rybakina managed to stave off three break factors towards the tip of the opening set after which took management of the tiebreaker. However her errors mounted within the second set as Kudermetova started to dominate.
Rybakina regained management within the decider and surged to a 4-1 lead earlier than extra errors allowed Kudermetova to stage. However the Kazakh participant rallied once more to take a decent service maintain and shut out the match.
She is going to face Jasmine Paolini after the Italian upset seventh-seeded Ons Jabeur 7-6 (8), 6-4.
Sixth-seeded Markéta Vondroušová additionally reached the quarterfinals after seeing off Anastasia Potapova 7-6 (5), 6-1. The Wimbledon champion has lined up second-seeded Aryna Sabalenka.