Li, the world No. 3-ranked women's player, needed a pair of breaks in each set to get by Zvonareva 7-5, 6-3. Li had seven double faults and Zvonareva managed eight break chances but Li finished off four of her own break opportunities.
Tuesday marked the first WTA match in 17 months for Zvonareva, who had been sidelined due to illness and a shoulder injury.
Fifth-seeded Peng Shuai, the second-highest ranked Chinese player after Li, advanced to the third round with a 6-3, 6-3 decision over Silvia Soler-Espinosa. Peng cashed in four of her five break points, also getting two breaks in each set.
Chan Yung-Jan posted an upset of sixth-seeded Zhang Shuai -- the third highest ranked women's player in China. Chan had three of her eight breaks in the third set of a 3-6, 6-4, 6-2 win.
Monica Niculescu rallied to a 4-6, 6-2, 6-3 first-round win over Anna Schmiedlova behind four third-set breaks. Also in the first round, Nadiya Kichenok built a 6-0, 2-0 lead, losing only 14 points in the eight games, before Timea Babos retired.
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