TOKYO, Japan - After compiling one of the best summer hardcourt seasons on the WTA, Agnieszka Radwanska was stunned in the second round of the US Open three and a half weeks ago by a No.92-ranked Angelique Kerber - she got some good old fashioned revenge in Tokyo on Tuesday afternoon.

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Radwanska, the No.9 seed at the Toray Pan Pacific Open, came from a set down to beat the now-No.33-ranked Kerber, 36 63 63, having actually lost their last two meetings - the German also defeated her at Beijing last year.

"I knew it was going to be a tough match today. We always seem to end up playing three tight sets," Radwanska said after the match. "Even though it wasn't easy, I managed to get some revenge from the US Open, so I'm very happy about that. Angelique has been playing very well the last few weeks."

After Kerber won a routine 32-minute first set, Radwanska set a strong tone at the beginning of both the second and third sets, storming out to 2-0 leads and never falling behind again in either set. "I played better in the second and third sets," she added. "I focused on every point and tried to be consistent until the end. We had some very close games; I just think I was better on key points."

Next up for Radwanska will be the No.8 seed, Jelena Jankovic, who won her second round match on Monday. Jankovic won their only previous meeting.

"Our last match was a long time ago," Radwanska said. "This is a really big tournament and almost everyone is here, so no match is going to be easy."

Two other seeds weren't so lucky in their second round matches, with No.11 seed Anastasia Pavlyuchenkova falling to Vania King, 64 76(6), and No.16 seed Shahar Peer falling to Klara Zakopalova, 63 61. It was a tight finish for King, who squandered double match point at 64 54 but managed to close Pavlyuchenkova out in a close tie-break, winning it on her fourth match point.

Also taking the courts of the Japanese capital earlier in the day were the last six first round matches of the tournament. No.10 seed Peng Shuai, No.14 seed Dominika Cibulkova, Tsvetana Pironkova, Christina McHale, Iveta Benesova and American qualifier Coco Vandeweghe were the winners, and all of them took the court again later for their second round matches.

The first round of the doubles event continued, with No.1 seeds and new US Open champions Liezel Huber and Lisa Raymond among the winners. They beat Japanese wildcards Rika Fujiwara and Ayumi Morita, 61 63.

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