Olympic 200m butterfly champion Liu Zige may miss the 100m at London 2012 after finishing third at  China nationals in Shaoxing today, the crown going to Lu Ying, of Shanghai, in 57.48, the silver to world 200m champion Jiao Liuyang, Guangzhou Army, in 57.80, locking Liu out by 0.05sec.

Lu first kept Liu out of the 100m at a major international last year and went on to clock 57.06 for bronze in the final at a home world championships in Shanghai. Lu told Xinhua that she may be a threat now to the top two in the 200m, saying: "I caught a cold, so the result is not good. I think I can improve it in the following days."

Jiao said she was not at her best on her way to working for a podium, place at London 2012, while Xinhua reported the following on the 200m Olympic champion: "Liu, who always keeps low profile towards the media, didn't say a word."

In another result that hinted at a change of guard, Fu Yuanhui, of Zhejiang and cheered on by a strong local crowd, cracked the minute to win the 100m backstroke in 59.99, silver going to one of China's top two backstroke aces in the past couple of years, Gao Chang, Shandong, on 1:00.68, with Zhao Jing, Hubei, in 5th behind Zhou Yanxin, Shanghai, 1:00.80, and Cheng Haihua, Beijing, 1:01.08. 

Fu, 15, entered the world rankings for the first time last year and ended the year with a best time of 1:00.27. Zhao's 1:01.27 is well away from the all-time fastest textile suit time of 58.94 that she set in 2010. Chinese nationals, however, are not the only event at which the nation's London 2012 Olympic team will be selected.

Zhao, the Asian record holder, explained  her poor form when she said: "I have a fever." That may be taken into account by selectors. 

The session also saw world 1500m freestyle champion Sun Yang, Zhejiang, clock 7:47.11 to win the non-Olympic 800m freestyle. "I take part in the 800m free to prepare for the 200m free Friday," said Sun, who seemed indifferent about the gap. "I just take it as a warm-up."

In the men's 100m butterfly, Zhou Jiawei, Guangdong, clocked 52.26 for victory ahead of Chen Weiwu, Shandong, on 52.51, 0.05sec ahead of Zhang Qibin, the Shandong swimmer who was the last inside 53sec. The men's 200m medley crown featured a man normally seen in the 100m butterfly: Wu Peng, Zhejiang, took the crown in 1:59.50, the minor spoils lifted by Yang Zhihe, Hunan, 2:00.23, and Wang Shun, Zhejiang, 2:00.59.

"I had planned to compete in the 100m fly, but it would be too tired for me to take part in two events in one night," Wu told Xinhua. "I had to choose one and I'm happy that I reached the Olympic A standard in the IM." His focus at London 2012 will be the 200m butterfly in which Michael Phelps (USA) could become the first swimmer ever to retain the title twice.

Results at a glance:

Women's 50m breaststroke:

• 1. Liu Xiaoyu, Liaoning, 31.39
• 2. He Yun, Shanxi, 31.77
• 3. Suo Ran, Chinese Navy, 31.78
• 4. He Yuzhe, Zhejiang, 31.79
• 5. Zhang Hongtao, Chinese Navy, 31.94

Women's 100m butterfly:

• 1. Lu Ying, Shanghai, 57.48
• 2. Jiao Liuyang, Guangzhou Army, 57.80
• 3. Liu Zige, Shanghai, 57.85
• 4. Gong Jie, Guangzhou Army, 58.70
• 5. Sun Mengyue, Chinese Navy, 58.76

Men's 100m butterfly:

• 1. Zhou Jiawei, Guangdong, 52.26
• 2. Chen Weiwu, Shandong, 52.51
• 3. Zhang Qibin, Shandong, 52.56
• 4. Shi Feng, Shanghai, 53.05
• 5. Chen Yin, Hebei, 53.55

Men's 800m freestyle:

• 1. Sun Yang, Zhejiang, 7:47.11
• 2. Wang Kecheng, Hunan, 8:00.28
• 3. Zhang Yunxiang, Shandong, 8:04.94
• 4. Gao Xuelei, Hebei, 8:09.14
• 5. Bian Shaoqing, Sichuan, 8:09.51

Women's 100m backstroke:

• 1. Fu Yuanhui, Zhejiang, 59.99
• 2. Gao Chang, Shandong, 1:00.68
• 3. Zhou Yanxin, Shanghai, 1:00.80
• 4. Cheng Haihua, Beijing, 1:01.08
• 5. Zhao Jing, Hubei, 1:01.27

Men's 200m individual medley:

• 1. Wu Peng, Zhejiang, 1:59.50
• 2. Yang Zhihe, Hunan, 2:00.23
• 3. Wang Shun, Zhejiang, 2:00.59
• 4. Liu Weijia, Liaoning, 2:01.01

Women's 4X200m freestyle relay:

• 1. Shanghai, 7:54.76
• 2. Shandong, 7:56.36
• 3. Zhejiang, 7:57.76
• 4. Beijing, 8:00.96
• 5. Tianjin, 8:08.67