As he cracked a ceremonial cask of sake to officially open the Japan Open this week, local AIG company boss Robert Clyde admitted he was relieved to get his mind temporarily off the current world financial crisis.

"Believe me, it's a lot more enjoyable to focus on tennis right now," said the president and chief executive officer of the Japanese branch of the worldwide insurer whose independent American corporate arm was taken over by the government last month for 85 billion dollars due to a massive cash-flow problem.

Washington received 80 per cent of AIG shares in a move to shore up the company and instil customer confidence.

AIG has sponsored the men's and women's event which pays over one million dollars in combined prize money for the past seven year.

And tournament officials, well-aware that AIG companies in Asia keep separate accounts and deposit pools from the troubled US mother ship, insist that the tennis show remains relatively unaffected by the troubles across the Pacific.

While Clyde, at the helm in Japan for five years, was able to forget corporate life for an hour or so in Tokyo, officials in tennis are know that the multi-million-dollar spot relies on high finance and commerce just as like any other international business.

While cash-flow may not yet have been affected, top officials in the game admit they must keep an eye on the world economic crisis all the same.

"We have to be concerned? But sports tends to be recession-protected? There is always a lot of investment into sports," said women's WTA head Larry Scott at this week's 650,000-dollar event in Stuttgart.

Scott said that apart from AIG in Tokyo there are no major banks or insurance companies involved in tennis sponsoring, adding that the game was all about long-term relationships.

Porsche has sponsored the Stuttgart tournament for 31 years while rival Mercedes is ending a contract with the ATP in December after a decade.

With the WTA year-end championships being shifted to oil-rich Doha in November, sponsorships money appears to be flowing on a circuit which will raise total prize money to 85 million euros (130 million dollars) in 2009 from 71 million (103 million dollars) this year.

Britain's Lawn Tennis Association only last month signed a global sponsorship worth an estimated 45 million dollars with AEGON, a financial services company which will have naming rights to British events - save Wimbledon, obviously.

The men's ATP is confident that it's marketing will also carry on in the current troubling environment.

"Despite the current economic shape. The ATP World Tour remains in very good commercial shape," said a spokesman on Wednesday.

"We are almost unique as a sport in terms of our global reach - next season we will have 63 tournaments in 31 countries - which means regional economic difficulties do not affect us in the way they might national associations or leagues.

"We have a flexibility to be able to focus on many different areas of the world where there are good long term opportunities both financially and from a fan interest perspective."

He added that "our standard indicators of growth such as revenues, attendances and prize money levels on the ATP Tour have all continued to grow throughout 2008."

Over the last few months, the body has signed new sponsors and extended current contracts with companies including Italy's Enel, Ricoh of Japan and South African Airways.

New sponsors include Barclays as the new 35-million-dollar sponsor of the ATP World Tour Finals to be played in London from 2009.