China's Li advances amid upsets at Shenzhen
File photo shows China's Li Na returning the ball to Serena Williams of the US during their WTA Championships final in Istanbul on October 27, 2013
The 31-year-old Li, the tournament's top seed, downed Kichenok 6-1 6-4 in second-round action at the Longgang Tennis Centre in the southern Chinese city of Shenzhen.
Li, Asia's highest-ranked player in tennis history, was coming off a victory Tuesday over Russia's Vera Zvonareva, once ranked number two in the world.
In the day's biggest upset, Vania King of the United States downed number two seed Sara Errani of Italy 2-6 7-6 6-3.
Patricia Mayr-Achleitner of Austria, meanwhile, upset third-seeded Klara Zakopalova of the Czech Republic in straight sets 7-6 6-4.
Romania's Monica Niculescu came from behind to beat Taiwan's Chan Yung-jan after dropping the first set 2-6. Niculescu took the last two 6-3 6-0.
In quarter-final doubles action, Niculescu and Zakopalova beat top seeds Zhang Shuai and Zheng Saisai of China 6-3 6-4.