- 16 Aug 08, 09:07 AM
Four years on from dropping out of an Olympic marathon she was clear favourite to win, Radcliffe lines up in Tiananmen Square on Sunday morning with no-one - not even herself - really knowing how she might perform.
Radcliffe says it's a case of "unfinished business". Unfortunately, after the foot injury, stress fracture and rogue spider bite that have prevented her from racing for the last nine months, her training and preparation are also incomplete.
She arrived in Athens having smashed the world record in her previous marathon and set a new British record over 5,000m less than two months before. Out here in Beijing, she's not so much undercooked as still in the pantry.
Marathons are the least forgiving of all athletics events. To do well anywhere - let alone in the heat and humidity of Beijing - you need miles in your legs, months of consistent distance-running followed by five or six weeks of shorter, faster efforts and tapering.
Radcliffe, instead, has been forced to do much of her work in the pool and on an anti-gravity treadmill, pushing hard right up until race-day.
Had this been a world championships or big city marathon, she'd almost certainly not be taking part. But after coming away empty-handed from three Olympics already, the emotional pull of the Games on the 34-year-old Radcliffe is immense.
My BBC colleague Steve Cram can sympathise. Having won the world 1500m title in 1983, he went to the Olympics the following year still in the process of recovering from injury.
"Mentally, there are similarities," he reckons. "You go out there not quite knowing what could happen.
"You have to try to have faith in your own abilities, in what you've achieved in the past.
"But it was far easier for me. You can run the 1500m without having the perfect preparation - you know that you'll at least be in touch until the final 200m or so.
"It's not the same in the marathon. There's a big difference between being fit enough to start and being fit enough to win a medal.
"Paula will have a problem with her strategy. All athletes want to run the way they're used to, the way they like.
"If she'd run 2hrs 21 mins in London in April, she'd have a plan of what she could do. But that didn't happen."
Cram came away from Los Angeles with a silver medal behind the man who had also beaten him four years earlier, Sebastian Coe.
Radcliffe will at least not have to face Japan's Mizuki Noguchi, the woman who stood atop the podium in Athens while she was being taken away in an ambulance.
In the injured Noguchi's absence, the marginal favourite out here is China's 2007 world silver medallist Zhou Chunxiu, the farmer's daughter who is reputed to run a staggering 187 miles per week over the winter.
But if all marathons are notoriously hard to predict, the Olympic race is doubly so. The Olympic record is almost five minutes slower than Radcliffe's world record.
History indicates that it's often not so much the best marathon runner in the world who wins as the athlete best prepared on that exact day for that specific course and conditions.
World record holder Haile Gebrselassie won't even be lining up in the men's race, fearful that the air pollution will exacerbate his asthma.
In Beijing, where the course loops around Tiananmen before heading north-east past the Temple of Heaven and Summer Palace and back round to the Bird's Nest, some sages are tipping Catherine Ndereba, world champion and winner of the New York half-marathon last month.
Ethiopia's Gete Wami, who beat Radcliffe over 10,000m at the Sydney Olympics, has the experience to convince others, while other whispers say Romania's Constantina Tomescu-Dita is in the form of her life.
Then there's the strange case of the British runner with the Kenyan and Japanese name, Mara Yamauchi.
Born in Oxford, she was brought up in Kenya, her parents naming her after a river that flowed near their house.
As Mara Myers she graduated from Oxford University and the LSE, took a job with the Foreign Office and went to work in the British embassy in Tokyo, at one point acting as interpreter for Baroness Thatcher and running the embassy's World Cup office in 2002.
While there she met and married Shigetoshi Yamauchi.
Having been a fine cross country runner before leaving England, she started training again seriously under a flexible working scheme which enabled her to job-share and then work part-time.
Since then she's gradually developed into one of Britain's finest-ever marathon runners. In the past year alone she's won the Osaka Marathon and finished fifth on a test event held on the Olympic course here.
While her PB of 2:25:10 is almost 10 minutes slower than Radcliffe's, there are those out here who believe she has the better medal chance of the two.
"Paula's the better runner, but Mara is better prepared," says Cram.
"The athletes who beat Mara at the Worlds last year (Yamauchi finished ninth) are here, and they've run faster than her.
"But she was the top British female last year, and she wants to improve against the rest."
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