Zhang Ning VS Maria Kristin women's singles semifinals Beijing Olympic Games

China's defending champion Zhang Ning snuck into the semi-finals of the Olympic badminton competition on Wednesday, defeating France's Pi Hongyan in a gripping three-game tussle.

Zhang, the veteran of the Chinese team at 33, was forced to fight all the way against the tenacious Pi after surrendering a one-game lead, before holding on for a 21-8, 19-21, 21-19 victory.

Zhang meets Indonesia's unseeded surprise package Maria Kristin Yulianti, who downed the Olympic champion at this year's Indonesian Open.

Yulianti, ranked 21 in the world, produced a gritty comeback in her quarter-final clash against Indian teenager Saina Nehwal.

Yulianti clawed her way back from one game down for a 26-28, 21-14, 21-15 victory over Nehwal, who was looking to become the first Indian woman to reach the last four.

"I don't know what happened after the first set, I just lost the match. Overall, it was a good game, but I just don't know what happened," the 18-year-old Nehwal said.

Nehwal pointed to a series of costly errors when she repeatedly allowed the shuttle to fall on the baseline only to see it called in.

Indonesia are gunning for at least one gold in Beijing, counting on their world champion men's and mixed doubles to come up with the goods.

But Yulianti, 23, has proved Indonesia are a chance on the women's side, downing Denmark powerhouse Tine Rasmussen on the road to the finals.