Kazakh Elena Rybakina, the No 9 seed, won against Czech qualifier Tereza Valentova 6-3, 7-6 (7) to advance to the third round of the US Open in New York on Wednesday.
Rybakina, ranked No 10, will face British woman and former US Open champion Emma Raducanu next at the USTA Billie Jean King National Tennis Center.
The Kazakh defeated American wildcard Julieta Pareja (6-3, 6-0) ahead of her win today.
In the previous round, Valentova, ranked No 94, edged out Italian Lucia Bronzetti (6-3, 3-6, 6-4).
New York (Grand Slam), other second-round matches (USTA Billie Jean King National Tennis Center, hard, USD 90,000,000):
Taylor Townsend beat Jelena Ostapenko (25): 7-5, 6-1
Barbora Krejcikova beat Moyuka Uchijima: 6-4, 6-2
Jessica Pegula (4) beat Anna Blinkova: 6-1, 6-3
Cristina Bucsa beat Alexandra Eala: 6-4, 6-3
Victoria Azarenka beat Anastasia Pavlyuchenkova: 6-3, 6-3
Emma Navarro (10) beat Catherine McNally (WC): 6-2, 6-1
Emma Raducanu beat Janice Tjen (Q): 6-2, 6-1
Amanda Anisimova vs. Maya Joint
Donna Vekic vs. Coco Gauff
Jaqueline Cristian vs. Ashlyn Krueger
Daria Kasatkina vs. Kamilla Rakhimova
Renata Zarazua vs. Diane Parry
Anastasia Zakharova vs. Laura Siegemund
Hailey Baptiste vs. Naomi Osaka
Sorana Cirstea vs. Karolina Muchova
Magdalena Frech vs. Peyton Stearns
Zeynep Sonmez vs. Marta Kostyuk
Suzan Lamens vs. Iga Swiatek
Anna Kalinskaya vs. Yulia Putintseva
Ekaterina Alexandrova vs. Xinyu Wang
Maria Sakkari vs. Anna Bondar
Beatriz Haddad Maia vs. Viktorija Golubic
Linda Noskova vs. Eva Lys
Aryna Sabalenka vs. Polina Kudermetova
Ann Li vs. Belinda Bencic
Iva Jovic vs. Jasmine Paolini
Elsa Jacquemot vs. Leylah Fernandez
McCartney Kessler vs. Marketa Vondrousova
Anastasia Potapova vs. Mirra Andreeva
Elise Mertens vs. Lulu Sun
Liudmila Samsonova vs. Priscilla Hon