Top seed Barbora Strycova has battled into the second round of the Ladies Open in Biel.
The Czech, ranked 18 in the world, needed three sets to get past her compatriot Marie Bouzkova 6-2 4-6 6-2 and set up a meeting with German Carina Witthoeft, who saw off Belinda Bencic 6-1 6-3.
Third seed Timea Babos is out, though, as she retired injured midway through the second set of her encounter with Evgeniya Rodina, trailing 7-6 (9-7) 4-2.
British pair Heather Watson and Naomi Broady were casualties as they both lost in straight sets.
Watson went down 7-6 (7-2) 6-2 to Anett Kontaveit and Broady struggled in a 6-4 6-2 loss to Julia Goerges.
Oceane Dodin, Marketa Vondrousova, Camila Giorgi and Aliaksandra Sasnovich were also winners.