Defending discus champion Li Yanfeng out of Moscow Worlds

Chinese women's discus world champion Li Yanfeng will not compete in the World Athletics Championships to be held Aug 10-18 in Moscow, owing to a waist injury.

"Li will not go to Moscow as she is still bothered by a waist injury and can not return to her best form," Li's coach Zhang Jinglong was quoted as saying by Xinhua on Monday.

The 34-year-old Li claimed the title at the 2011 Daegu Worlds in South Korea with a winning mark of 66.52 metres, delivering the first gold medal in field events for China since Huang Zhihong's victory in the women's shot put in the 1993 edition.

In the 2012 London Olympics, Li threw 67.22 metres to pocket a bronze, which could be upgraded to a silver as the runner-up Darya Pishchalnikova of Russia was tested positive for banned substance after the Games.

After the London Games, Li never managed to maintain systemic training because of the haunting lumbar disc herniation.

According to Zhang, Li only threw a best mark of 58.90m in a warmup in late July and achieved 60.12 in a provincial athletic meet in her hometown Heilongjiang Province last Sunday.

"Li is still not ready for high-level competitions like the World Championships. With her current form, Li even may not be able to make it from the qualification rounds," Zhang said.

"Although she already assured a berth in the worlds as the reigning champion, it will be meaningless or even a blow to her confidence for Li to compete in Moscow," he added.