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 US Open semi-finalist Jennifer Brady in the second round.

The American came from a set down to defeat Ukraine’s Dayana Yastremska 3-6 7-6 (8-6) 6-1.

Another American, qualifier Coco Gauff advanced after edging wildcard Katerina Siniakova 7-5 6-4.

The 16-year-old will play third-seeded Aryna Sabalenka of Belarus in the next round.

Tunisia’s Ons Jabeur knocked out 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.