Tokyo - World No.1 Victoria Azarenka beat Italy’s Roberta Vinci to enter the quarterfinals of the Pan Pacific Open tennis event here Wednesday.
The Belarusian star had little problem dispatching the 14th seed in a 6-4, 6-2 victory in the third round.
In the quarters, the U.S. Open finalist will face Germany’s fifth seed Angelique Kerber, who breezed past Urszula Radwanska of Poland 6-1, 6-1.
Kerber will seek her first win in three encounters against Azarenka.
Third-seeded Agnieszka Radwanska, meanwhile, outdid her sister to knock out U.S. qualifier Jamie Hampton 6-4, 6-3.
In the next round, the 23-year-old Pole will meet 10th seed Caroline Wozniacki of Denmark.
Wozniacki had to dig deep to oust Li Na, seeded 7, surging back after losing the first set 4-6, 6-3, 6-4.
Elsewhere, second-seeded Maria Sharapova defeated Lucie Safarova of Czech Republic 6-2, 7-6(5) to reach the quarterfinals, where she will play eighth seed Sam Stosur.
The 28-year-old Australian player eliminated Slovakia’s Dominika Cibulkova 6-4, 7-5.
The last quarterfinal pair will see Sharapova’s compatriot Nadia Petrova playing against Italy’s Sara Errani.
Petrova, seeded 17, struggled past Croatia’s Petra Martic, racking up 15 aces to snatch a 7-6(2), (1)6-7, 6-4 win.
Sixth-seeded Errani had nearly as difficult a test in her third-round match against France’s Marion Bartoli, pulling out the match from one set down 3-6, 6-2, 6-2.