Peng Shuai of China hits a return to Jelena Jankovic of Serbia during their match at the Australian Open tennis tournament in Melbourne January 20, 2011. REUTERS

MELBOURNE, Jan 20 - China's Peng Shuai knocked seventh seed Jelena Jankovic out of the Australian Open on Thursday, her 7-6 6-3 second round win providing the first genuine upset of the week at Melbourne Park.

Serbian Jankovic, a semi-finalist here in 2008, blew a lead of two service breaks in the first set before claiming a third to force a tiebreak, which she lost 7-3.

Peng, ranked 54th in the world after struggling with injury last year, broke for a 4-2 lead in the second and served out for victory three games later, dancing around the Hisense Arena court with a huge smile on her face.

Jelena Jankovic of Serbia hits a return to Peng Shuai of China at the Australian Open tennis tournament in Melbourne January 20, 2011. REUTERS

Jankovic was once again left ruing her inconsistency after serving up 39 unforced errors against her deceptively hard-hitting opponent.

Peng's triumph continues China's good showing in the women's draw at the Australian Open, now officially titled the "Grand Slam of the Asia/Pacific".

Her compatriots Li Na and Zheng Jie both reached the semi-finals last year. Ninth seed Li reached the third round on Wednesday with a comfortable 6-3 6-2 victory over Evgeniya Rodina of Russia, while Zheng missed the tournament through injury.