PRAGUE — Third-seeded Iveta Benesova of the Czech Republic defeated Monica Niculesco of Romania 7-5, 6-4 Thursday to advance to the quarterfinals of the Prague Open.

Benesova will face Zarina Diyas of Kazakhstan, who upset eighth-seeded Petra Kvitova of the Czech Republic 6-4, 6-2. The 15-year-old Diyas, ranked 295th, reached her first quarterfinal of a WTA event.

Also, Kateryna Bondarenko of Ukraine edged Kristina Barrois of Germany 7-5, 7-5, and will play top-seeded Francesca Schiavone of Italy.

Timea Bacsinszky of Switzerland beat Stefanie Voegele of Switzerland 6-4, 6-1.