Tokyo: Two-time champion Maria Sharapova advanced to the third round of the Pan Pacific Open by beating British qualifier Heather Watson 6-7 (7), 6-3, 6-4 on Tuesday.
The seventh-seeded Li Na and fifth-seeded Angelique Kerber also won, but 2011 Wimbledon champion Petra Kvitova, the fourth seed, was upset by Petra Martic of Croatia 6-4, 6-4.
Top-ranked Victoria Azarenka faced Tamira Paszek of Austria late Tuesday, as did former No. 1 Caroline Wozniacki against Daniela Hantuchova.
Two-time champion Maria Sharapova advanced to the third round of the Pan Pacific Open by beating British qualifier Heather Watson.
Watson pushed Sharapova to three sets in their last match at the 2011 U.S. Open, and did it again by winning a marathon tiebreaker in the first set.
The second-seeded Sharapova, who won here in 2005 and 2009, took control of the third set when she broke Watson's serve for 4-3. She sealed the win when Watson sent a forehand return long.
Li defeated Anastasia Pavlyuchenkova of Russia 7-5, 4-6, 6-2, and awaited Wozniacki or Hantuchova, while Kerber of Germany downed Ayumi Morita of Japan 6-3, 6-4.
Also through were Marion Bartoli of France and Nadine Petrova of Russia.