The upsets continued at the J&T Banka Ostrava Open as second seed Karolina Pliskova crashed out at the hands of qualifier Veronika Kudermetova.
At an event in her native Czech, the former world number one slumped in the second set, and the Russian powered through, 4-6, 6-4, 6-3.
It was the second win over Pliskova in as many months for Kudermetova, who had already beaten Pliskova back in August at the Western and Southern Open.
Pliskova went the way of Elina Svitolina, the top seed, who lost in straight sets to Maria Sakkari of Greece yesterday.
The third seed, however, had better fortune - Belarus's Aryna Sabalenka fought past highly-rated teenager Coco Gauff of the USA, 1-6, 7-5, 7-6(2).