TOKYO (AP) -- A resurgent Caroline Wozniacki advanced to the second round of the Pan Pacific Open on Tuesday while gaining revenge over Belinda Bencic for last year's semifinal defeat.
Continuing the form that took her to the U.S. Open semifinals, Wozniacki hit 10 aces in the 6-2, 5-7, 6-1 win over Bencic to set up a second-round meeting with fourth-seeded Carla Suarez Navarro.
The result ended a run of four straight defeats for Wozniacki against the Swiss player.
Yulia Putintseva of Kazakhstan upset fifth-seeded Madison Keys of the United States 6-3, 3-6, 7-6 (7) while facing down 15 aces, and sixth-seeded Dominika Cibulkova of Slovakia ousted Lucie Safarova of the Czech Republic 4-6, 6-1, 7-5 on a drop shot after 2 1/2 hours.
The 2013 champion Petra Kvitova of the Czech Republic beat Madison Brengle of the United States 6-3, 6-3 to set up a meeting in the second round with Rio de Janeiro Olympic champion Monica Puig of Puerto Rico.