Zhang Ning returns the shuttlecock to Salakjit Ponsana of Thailand (not pictured) during their women's singles second round badminton match of in Beijing August 10 2008. Zhang won 21-23 , 21-17 , 21-7. [Agencies]

Defending Olympic champion Zhang Ning of China recovered from a shaky start Sunday to defeat Thailand's Salakjit Ponsana in three sets at the Olympic badminton tournament.

Second-seeded Zhang defeated Ponsana 21-23, 21-17, 21-7 to advance to the third round of the women's singles tournament at the Beijing University of Technology Gymnasium.

"I wasn't too worried after losing the first set," said Zhang, who had a first-round bye. "I've played her before so I knew what to expect."

Zhang is seventh in the world rankings and has struggled with injuries this year but was picked over 2007 world champion Zhu Lin, who is third in the world rankings.

The 33-year-old Zhang was rusty in the first set but quickly took control of the match with smashes that were too powerful for her 29th-ranked opponent.

Zhang will next face South Korea's Jun Jae-youn, a 21-12, 21-14 winner over Chloe Magee of Ireland.

China won three of five gold medals in badminton at the Athens Olympics in 2004 and is expected to dominate on home soil.

Sunday was the first day China's players were in action and the capacity crowd was in full voice in support of their players, waving Chinese flags and shouting "Go China!"

In other matches, sixth-seeded Tine Rasmussen of Denmark coasted to a 21-6, 21-8 win over Akvile Stapusaityte of Lithuania and fifth-seeded Pi Hongyan of France defeated Peru's Claudia Rivero 21-6, 21-9.

In a men's singles first-round match, South Korea's Park Sung-hwan defeated Canada's Andrew Dabeka 21-11, 21-11.

China's Lin Dan is seeded No 1 in the men's singles and will play his first match in the second round today against unseeded Ng Wei of Hong Kong.

In women's doubles, defending Olympic champions Yang Wei and Zhang Jiewen of China defeated Indonesian pair Liliyana Natsir and Marissa Vita 21-19, 21-15 to advance to the quarterfinals.

The formidable pair downed Indonesia's Vita Marissa and Liliyana 21-19, 21-15 in the round of 16.

China has won women's doubles gold at the last three Olympics, and the world champions and No 1 seeds conceded to feeling slightly nervous in their first outing.

"It is a tough game. I felt a little stiff in the beginning of the match. (But) is normal to feel a bit nervous," said Yang, who also won silver with her former partner in Sydney.

In other doubles matches, Singapore's Jiang Yanmei and Li Yujia downed the USA's Eva Lee and Mesinee Mangkalakiri 2-0.

Japan's Miyuki Maeda and Satoko Suetsuna walked over Australia's underdogs Tania Luiz and Eugenia Tanaka 2-0.

Agencies