Venus Williams rallied from a set down to defeat Simona Halep of Romania 4-6, 7-5, 6-3 on Wednesday and reach the quarterfinals of the Pan Pacific Open.
Williams, making her first appearance in the Tokyo tournament since 2009, broke serve to lead 5-3 in the third set at Ariake Colosseum and then won with a crosscourt forehand that No. 13-seeded Halep hit into the net.
"It was a very tough match," Williams said.
"She played very well. I don't know how I was able to win the match. I just wanted to stay in Japan longer."
She played very well. I don't know how I was able to win the match. I just wanted to stay in Japan longer
Williams, who ousted top-seeded Victoria Azarenka on Tuesday, will face Canada's Eugenie Bouchard in the quarterfinals.
Bouchard upset sixth-seeded Jelena Jankovic of Serbia 7-5, 6-2. Making her debut in the Tokyo tournament, Bouchard broke Jankovic to go up 5-2 in the second set and then held serve to win.
Jankovic had a 5-4 lead in the first set but Bouchard won the last three games after a talk with her coach.
"I felt like I wasn't playing my best in the first set," Bouchard said.
"But I stayed with her and started to get a lot more aggressive near the end of the first set and that was the turning point."
Bouchard, who is 46th in the world rankings, said winning last year's junior Wimbledon title has given her confidence to compete at a higher level.
"That gave me a lot of confidence to play in the pros," Bouchard said.
"Playing week in, week out against the top players has made me a better player."
In other third-round matches, fourth-seeded Caroline Wozniacki defeated Magdalena Rybarikova 6-1, 6-1, and second-seeded Agnieszka Radwanska beat Dominika Cibulkova 6-3, 6-4.
Fifth-seeded Angelique Kerber of Germany overpowered No. 11-seeded Ana Ivanovic of Serbia, 6-4, 6-2, and Lucie Safarova of the Czech Republic beat No. 12-seeded Samantha Stosur of Australia, 6-4, 6-4.