Zverev defeats Hanfmann to begin Munich Open title defense

Alexander Zverev began his Munich Open title defense with a 6-7 (12), 6-4, 6-2 win over Yannick Hanfmann on Wednesday.

The top-seeded Zverev needed over two hours to prevail over the 118th-ranked Hanfmann, a wild-card entry, and set up a quarterfinal against Jan-Lennard Struff.

Struff defeated German compatriot Yannick Maden 6-3, 3-6, 6-3.

The fourth-seeded Chung Hyeon progressed with a 6-1, 61 second-round win over Matthias Bachinger and will next face 2014 tournament-winner Martin Klizan.

Klizan defeated Mirza Basic of Bosnia-Herzegovina 4-6, 6-3, 7-5 earlier Wednesday.

Petra Kvitova cruises into Prague Open quarterfinals

Second-seeded Petra Kvitova cruised into the quarterfinals of the Prague Open with a 6-3, 6-1 victory over unseeded Russian Natalia Vikhlyantseva on Wednesday.

Kvitova will face fellow Czech Katerina Siniakova, who prevailed 6-4, 3-6, 6-3 over another Russian, Ekaterina Alexandrova.

Sixth-seeded Shuai Zhang of China eliminated Romanian qualifier Elena-Gabriela Ruse 64, 6-4, wile seventh-seeded Mihaela Buzarnescu dispatched another qualifier, Antonia Lottner of Germany, 6-0, 7-6 (7).

Former finalist Samantha Stosur advanced to her first WTA quarterfinal this year with a 6-4, 6-4 victory over Czech Denisa Allertova. The Australian will face Italian Camila Giorgi, who dismissed Tamara Korpatsch of Germany 6-4, 6-2.

Kristyna Pliskova also made the quarters by defeating Qiang Wang of China 6-2, 7-6 (3) and Jasmine Paolini of Italy beat Anna Karolina Schmiedlova of Slovakia 6-4, 6-1.