TIANJIN, China (AP) — Top-seeded Jelena Jankovic was upset by Zheng Saisai of China 6-3, 6-3 in the second round of the Tianjin Open on Thursday.

The 112th-ranked Zheng converted five of nine break points against Jankovic to notch her first career win over a top-20 player.

Hometown favorite Peng Shuai, seeded second, also advanced to the quarterfinals with a 6-1, 6-2 win over qualifier Elizaveta Kulichkova of Russia. Peng, the top-ranked Chinese player now that Li Na has retired, reached the U.S. Open semifinals last month but is still looking for her first WTA Tour title.

Also, Hsieh Su-Wei of Taiwan topped fifth-seeded Zhang Shuai of China 3-6, 6-3, 7-6 (5).

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