 Complete the following phrase:  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 Indonesias 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 