Top-seeded Marion Bartoli of France and sixth-seeded Monica Niculescu of Romania were knocked out in the first round of the Guangzhou Open on Tuesday.
Taiwanese qualifier Kai-Chen Chang was leading Bartoli 4-3 when the Frenchwoman retired with an injury. Mathilde Johansson of France defeated Niculescu 7-5, 6-2. The 27-year-old Johansson won despite 12 double-faults.
Second-seeded Zheng Jie of China, third-seeded Sorana Cirstea of Romania and fourth-seeded Urszula Radwanska of Poland also advanced.