Radcliffe and Olympic champion Noguchi racing against time

Noguchi, who would become the first woman to defend the crown, is fighting a battle against severe fatigue to ensure there is a Japanese winner for the third successive Games - after Naoko Takahashi's win in Sydney eight years ago.  

But Radcliffe is realistic enough to realise she faces a massive challenge in Beijing, with or without Noguchi.  

Catherine Ndereba and Deena Kastor, silver and bronze medallists in Athens four years ago, are in the best shape of their careers - while world marathon majors champion Gete Wami is also reported in flying form.  

Champion: Noguchi

Hopeful: Radcliffe

Kastor has looked especially sharp in the build-up to her third Olympics, at the USA pre-Games camp in Dalian.  

But Noguchi is regarded as the greatest threat to Radcliffe, hoping to atone for dropping out at the last Games with only six kilometres of the race remaining. 

Radcliffe is determined to compete after injuring her left thigh - and believes she can pull off what medical experts consider an impossible dream, after cross-training in the gymnasium and swimming pool at her Font Romeu base in the French Pyrenees. 

The world marathon record-holder has been running every day without any problems from the injury since her arrival at the British Olympic Association holding camp in Macau last Monday. 

Noguchi has been less fortunate. She secretly returned from her favourite training base in St Moritz on August 4 and has been undergoing tests for her problem at a hospital in Kyoto.  

The illness saw the Olympics' smallest champion - she stands 4ft 11in and weighs 90lbs - back home earlier than planned.  

Normally before every major marathon race, Noguchi comes down from sea level 10 days beforehand.  

But her schedule changed last week when she returned from the high altitude Swiss resort on August 4 - three days earlier than expected.  

Noguchi has undergone several MRI tests, her advisers trying to establish what is causing the tiredness in her muscles which caused concern in her final build-up to Beijing.  

'She has now been released and is being advised by a team of doctors,' an official told reporters.  

'We are now trying very hard to get her together for the race.' 

An announcement is expected to be made by the Japanese federation very shortly as to whether Noguchi will travel as planned to Beijing on Wednesday - or even decide she is not in condition to challenge for a second successive gold medal.