OSTRAVA, Czech Republic -- Qualifier Daria Kasatkina upset sixth-seeded Elena Rybakina 6-2, 3-6, 6-3 to advance to the second round of the Ostrava Open on Tuesday.
Kasatkina broke 19th-ranked Rybakina for a 3-1 lead in the deciding set and held her serve on the way to her first win over a top 20 player this season.
Kasatkina will face U.S. Open semifinalist Jennifer Brady in the second round. The American came from a set down to defeat Ukraine's Dayana Yastremska 3-6, 7-6 (6), 6-1.
Another American, qualifier Coco Gauff advanced after edging wildcard Katerina Siniakova 7-5, 6-4. The 16-year-old will play next third-seeded Aryna Sabalenka of Belarus.
Also, Ons Jabeur of Tunisia eliminated Czech Barbora Strycova 6-2, 6-2, while her fellow Czech Karolina Muchova eased past China's Zhang Shuai 6-1, 6-1.
The inaugural Ostrava Open, an indoor hard-court event, was added to the WTA tour after the tournaments in China were cancelled due to the coronavirus pandemic. It's being played without spectators.
