It was a perfect marketing opportunity: as the Olympic torch made its way through 113 Chinese cities in a stage-managed procession given pride of place by China's media, Mengniu, a dairy group, swept through the country with its own sports-focused promotions.

It sponsored a television show, Among the Cities, that capitalised on the Olympic hype by searching for the country's best amateur athletes. The sponsor's slogan: “Drink more milk and play more sports - everyone will be his own health champion.”

But all was not as it seemed. Although a study by Ipsos, the market researcher, this year found that respondents thought that Mengniu was one of the top five Olympic sponsors, it isn't. The official dairy sponsor is Inner Mongolia Yili Industrial Corporation (Yili), its rival, and it had been, to use the jargon, ambushed.

Indeed, Olympic ambushers have become the corporate bad boys of the Beijing Games. For the privileged few who have stumped up the $100 million-plus to have their names associated with the event, those brands that try to muscle in on the action have proved to be a problem.

The motivation is obvious: there are 1.3 billion consumers in China and key television programmes in the country can be watched by up to 300 million people. It is a marketeer's dream. Moreover, a study by the China Market Research Group suggested that consumers do not necessarily remember which brands are “Olympic”. The survey found, for example, that 60 per cent of the Chinese population thought that Pepsi was the official drinks sponsor of the Games - a blow to Coca-Cola, which has invested hundreds of millions of dollars in the event.

“Pepsi was a sponsor of the 2007 Asian Games and was within its rights to use a 'Team China' message until the end of the year,” Matthew Brosenne, business development director of CSM Media Research in China, said. “Pepsi also released a new can coloured 'China red'.”

However, Mr Brosenne added, the sponsors had been fighting back. Yili reacted quickly to Mengniu's challenge with a series of advertisements with the slogan: “Beijing 2008 Olympic Games Sole Dairy Products Sponsor.”

“They took measures to better differentiate themselves from their competitor in their packaging. The result? They clarified the confusion dramatically,” Mr Brosenne said. But Yili's eventual success will do little to dissuade the ambushers from striking again at future Olympics.

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