Head coach of the Chinese gymnastics team said in Hong Kong on Saturday that they might not be able to repeat the 2008 feat in the London Olympics.
Huang Yubin admitted "it is impossible to nurture a new all-around star" before the 2012 Games.
The leading all-arounder usually plays a vital role in the team event.
The Chinese team peaked in the Beijing Olympics by sweeping seven men's and two women's gold medals.
Huang expected the Chinese team to face a tough challenge in London, mainly because of the retirement of the so-called "Diamond Generation".
Li Xiaopeng, Yang Wei and Huang Xu, considered as polished diamonds by Huang, all called it quits after the Beijing Games.
"What made the trio so special and precious is that they were all-arounders and very important in the team competitions, but now I have seen none like them in the young generation," Huang said at a news conference here before a Charity Extravaganza.
Huang added other Olympic champions like "Rings King" Chen Yibing, Xiao Qin and triple Olympic winner Zou Kai all have weak points.
"It's not easy to discover a promising all-arounder, and I have little confidence in finding a new lead man before the London Olympics," said Huang.
Huang also lamented about the retirement of experienced coaches after the 2008 Olympics.
"I am worried about the level of local coaches," he said. "I have prepared for a slip of results in London."