Radcliffe, who will be 38 by the time of the London Games, has established herself as a world champion and world record holder at the marathon, but despite competing in the last four Olympics, she has been unable to win a medal on the track or the road, coming closest with fourth place in the 10,000m at the 2000 Sydney Games.

O’Sullivan, who outsprinted Radcliffe to the long course World Cross Country title in 1998 before completing the double with the short course gold, is overall manager and coach of the Australian team at this weekend’s World Cross Country Championships in Bydgoszcz and will be Ireland’s Chef de Mission at the 2012 Games.

"I think it will be very difficult for Paula to really impact on the marathon in London 2012," said O’Sullivan, who took her three teams and two junior women out for training at her old haunt of Bushy Park, Teddington on Tuesday before flying out to Poland.

"I think Paula has really hammered her body over the years and marathon training really takes a huge toll of wear and tear on the body.

"If Paula trained for the marathon just to win it then she would have a better chance that always trying to go out and run the world record.

"She already has the world record so it seems pointless to be killing yourself to chase an already impossible time for the best women marathoners in the world.

"Paula needs to train more conservatively and limit her big marathon efforts over the next few years if she is to be competitive in London.

"I don’t speak to Paula regularly but I have spoken to her in the past when she was training while pregnant and again afterwards and when she had some similar injury problems that I had after my first daughter Ciara was born."

Meanwhile O’Sullivan says that she has something in common with Roy Keane, who played for Cobh Ramblers, her home town team, for whom her father, John, was goalkeeper.

"I think we both have steely determination and the desire to be the best," she said.

"I rarely left any stones unturned when chasing my goals - often maybe turned a few too many and went beyond what was required.

"This blinkered ability to focus, I see it in Roy Keane when he played football and as a manager.

"I think I also have this drive to achieve great results and strive for perfection in my performance both as an athlete and in also trying to influence positive energy through other athletes that I am involved with."

To read a full interview with Sonia O'Sullivan click here.

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