SHANGHAI - Yao Jinnan, the backbone of Chinese women's gymnastics team, has dropped out of the National Championships here due to a slight knee injury but remains high hopes of making into the Olympic line-up.

Yao, women's all-around bronze medalist in the 2011 world championships, bruised her knee ligament during her training session on Monday when she was doing a vault routine, according to her coach Wang Qunce.

Wang stressed that it was not a big problem, saying he believes the 17-year-old's preparations for the Olympics should not be affected.

"Apparently it's not swollen and the MRI scan showed that the injury is not serious," said Wang. "She could return to training in one or two weeks,"

Despite the injury and withdrawal, Yao is widely regarded to be selected into China's Olympic squad for sure.

One of the best all-around gymnasts, Yao played a pivotal role when China pocketed the team bronze medal in the world championships in Tokyo last year. She also snatched the silver on the balance beam.

The National Championships is the most important Olympic trial but not the only chance for Chinese gymnasts to enter the Olympic lineup.

The trial panel will also take into consideration their performances in major international events as well as the results of closed team tests.

"Jinnan was eager to compete and she said 'I'm ok' after the injury," Wang said.

"But to protect her from aggravating the injury, we persuaded her to withdraw. After all, this championships is not the deciding tournament," he added.

The five-day National Championships will end on Saturday.

The Chinese Gymnastics Association is expected to announce later this month their final 14-strong lineup for the London Games, including two backups each for men and women.

Chinese women won their first-ever Olympic team title in the 2008 Games on home ground but in London, their chances to beat favorites America are considered slim.