Qualifier and former World No. 10 Daria Kasatkina of Russia upset sixth-seeded Elena Rybakina on Tuesday in the first round of the JT Banka Ostrava Open in the Czech Republic.
Kasatkina notched her best win in a year, defeating Kazakhstan's Rybakina 6-2, 3-6, 6-3 in one hour, 51 minutes.
"I can say that I beat her with tactics," Kasatkina said. "At the beginning I was trying to play a bit more aggressive to move her -- but she was the one who started to move me. During the match I changed the plan of my game and it worked out very well."
Kasatkina tallied 15 winners against just 14 unforced errors; Rybakina hit 35 winners and 49 unforced errors.
In other action, American Coco Gauff defeated Katerina Siniakova of the Czech Republic 7-5, 6-4; Ons Jabeur of Tunisia topped Czech Barbora Strycova 6-2, 6-2; Czech Karolina Muchova beat Shuai Zhang of China 6-1, 6-1; Veronika Kudermetova of Russia defeated Donna Vekic of Croatia 6-2, 6-4; and American Jennifer Brady outlasted Dayana Yastremska of Ukraine 3-6, 7-6 (6), 6-1 in two hours.
--Field Level Media