Russia's Svetlana Kuznetsova avenged a shock defeat by China's Li Na at the Beijing Olympics in the first round of the Pan Pacific Open on Wednesday.
The former US Open champion, toppled by Li at the first hurdle in Beijing last month, won 6-2, 1-6, 6-3 to reach the last 16 in Tokyo.
Fifth seed Kuznetsova, who helped Russia retain the Fed Cup in Spain at the weekend, wrapped up a tough win with a fizzing ace down the middle after one hour and 49 minutes.
"I played in Europe on clay on Sunday," an exhausted Kuznetsova told reporters. "I couldn't ask more of myself. I was in danger of losing because I wasn't 100 percent prepared.
"I've never had the experience of playing a Fed Cup final, then two days later coming out to play such a big tournament so far away -- and to play Li, who beat me at the Olympics."
Li went on to reach the semi-finals in Beijing, losing to Dinara Safina. The Chinese was beaten by another Russian, Vera Zvonareva, in the bronze medal playoff.
Serbia's Jelena Jankovic heads a strong field in Tokyo including six of the world's top 10 players and will regain the number one ranking from Serena Williams if she wins the $1.34 million tournament.
Jankovic, fellow-Serb Ana Ivanovic and Russia's Olympic champion Elena Dementieva all play on Thursday after receiving byes into the second round.
Fourth seed Safina was playing her opening match later on Wednesday against Slovakia's Dominika Cibulkova.
In other matches, Slovenia's Katarina Srebotnik brushed aside Caroline Wozniacki of Denmark 6-1, 6-2 while Frenchwoman Virginie Razzano ousted Japan's Ai Sugiyama 6-3, 6-2.
Meanwhile, Russian Nadia Petrova beat France's Aravane Rezai 7-5, 6-2 to set up a meeting with Ivanovic.
