2003 Although she had previously won a number of international open titles dating from the mid-1990s, Zhang's breakthrough as a dominant player on the world circuit came in the
2003 IBF World Championships, where she stormed into the final. There, 28-year-old Zhang Ning defeated compatriot Gong Ruina easily 11-6, 11-3.
2004 The following year, Zhang played
badminton at the 2004 Summer Olympics for China. In women's singles, she defeated
Marina Andrievskaya of Sweden and
Kelly Morgan of Great Britain in the first two rounds. In the quarterfinals, Zhang beat
Wang Chen of Hong Kong 9-11, 11-6, 11-7 to advance to the semifinals. There, she defeated countrywoman
Zhou Mi 11-6, 11-4. Zhang defeated Netherlands's
Mia Audina 8-11, 11-6, 11-7 in the final to win the [gold medal. It was sweet revenge for the 29-year-old, who had lost to Audina 10 years earlier in the decisive match of the
Uber Cup. With her Olympic win, she became one of three singles players in the world to win the World Championship and the Olympic Games (in either order) in successive years, the others being
Susi Susanti and
Taufik Hidayat.
2005 Zhang also claimed many titles after her breakthrough wins. She bested
Xie Xingfang in the 2005
China Open 3-11, 11-4, 11-8, but in the
2005 World Championships final Zhang fell to
Xie Xingfang, 8-11, 11-9, 3-11.
2006 In 2006, Zhang reached the finals of the
World Championships yet again, but she was still unable to defeat Xingfang. This time, she lost 16-21, 14-21. However, Zhang claimed revenge in the
Japan Open, defeating Xingfang 21-11, 16-21, 30-29. This was the 19th time they had met in an international tournament, with the head-to-head tied at 9-9. During this year the well known Dutch documentary filmmaker Roel van Dalen made the documentary film
Olympic Journey - The Road to Beijing on the life of Zhang Ning, which was broadcast on television worldwide.
2007 In 2007, Zhang won her fifth
Singapore Open title in six times, beating Xingfang 21-18, 19-21, 21-3. In the World Championships, Xingfang was defeated in the third round by Malaysian
Wong Mew Choo, making Zhang a favourite for the title. However, she was stopped in the semi-finals by Wang Chen. This was the second time Wang Chen had beaten her in 2007, after the
Indonesian Open. Zhang's compatriot
Zhu Lin went on to beat Wang in the final 21-8, 21-12. In the Beijing Good Luck Invitational tournament, Zhang reached the semi-finals to face Zhu Lin but pulled out due to injury. In the
Danish Open, she reached the final, but lost 17-21, 14-21 to compatriot Lu Lan due to a thigh injury. Zhang also reached the semi-finals of the
French Open, but was upset by local hope
Pi Hongyan. In the
China Open, Zhang lost in straight sets to Malaysia's
Wong Mew Choo in the semi-finals. Zhang cited injury and fatigue as the main reasons for her loss.
2008 Zhang's 2008 season started with a first round loss in the Malaysian Open. She was seen coaching her younger teammates in the tournament as well. In the Korean Open, she lost to her former compatriot,
Zhou Mi, in the quarter-final. Zhou now plays for Hong Kong. In the All England, Zhang and Xie, the top 2 seeds, lost in the first round. However they both bounced back strongly in the Swiss Open to reach the final, for their 22nd international meeting. To be in the final was a relief for Zhang, who had failed to get past the quarter-finals in three previous tournaments. Still, Xie beat Zhang 21-18, 21-17, bringing their head-to-head stands to 11:11. Later, at the
Beijing Olympic Games, Zhang progressed to the quarter-final after overcoming South Korean
Jun Jae Youn in the third round. She then subdued fifth-seeded
Pi Hongyan of France and Indonesia's
Maria Kristin Yulianti 21-15, 21-15 to reach the final. There she faced compatriot and world number 1
Xie Xingfang and won in a tough three-setter, 21-12, 10-21, 21-18, to extend her gold medal reign. Zhang became the first badminton player to ever defend an Olympic singles title even though many questioned her ability to do so at the age of 33. She was additionally chosen to represent China as the flag bearer for the
2008 Summer Olympics closing ceremony. ==Retirement==