Bencic, Kvitova vying for semifinal spots in Day 5 at the St. Petersburg Ladies Trophy

After falling short in Adelaide earlier this year, the top seed faces sixth-seeded Maria Sakkari of Greece. Sakkari is into her first quarterfinal of the season, and will be meeting Bencic for the first time at the WTA level.

Defending champion Kiki Bertens will meet 18-year old Russian qualifier Anastasia Potapova for a spot in the semifinals. The second-seeded Dutchwoman is looking to defend a title for the second time in her career, after doing so in Nurnberg (2016, 2017).

Third-seeded Petra Kvitová faces a familiar foe in talented Russian Ekaterina Alexandrova. The 2018 champion defeated Alexandrova last month at the Australian Open and will be looking to repeat the performance.

Kazakhstan's Elena Rybakina squares off against French qualifier Oceane Dodin for the final semifinal spot. After upsetting fourth-seeded Jo Konta in the previous round, Dodin appears confident and seems to be playing with less pressure.