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Video - Plucky Paula digs deep in marathon
Paula Radcliffe has not ruled out one last attempt at Olympic glory in four years' time after finishing 23rd in Sunday's marathon in Beijing.
The 34-year-old was in tears as she crossed the finish line at the Bird's Nest Stadium after a gutsy performance.
"It's not the end," she said. "We'll keep our fingers crossed for 2012.
"Maybe the Olympics won't happen for me, but I can do it in 2012 if my body holds together. I guess that is what I need now, a bit of luck."
Team-mate Mara Yamauchi was the leading Briton as she came home sixth in a race won by Romania's Constantina Tomescu.
Radcliffe stopped two miles from home but still finished the race
Radcliffe's preparations for the 26.2 mile race were far from ideal as she valiantly sought a return to competition after suffering injury in May.
Having battled battled back from a stress fracture to her leg to compete, Radcliffe started well but faded and briefly stopped two miles from home with cramp.
The world record holder admitted she was not in the right shape coming to Beijing but pointed to 38-year-old winner Tomescu as her inspiration to compete at the London Games.
"I was trying to achieve the impossible I guess," she added. "The amount of running I've done coming in wasn't enough.
"But I didn't do all that work for nothing. It's just really frustrating.
"I knew I was pushing it coming in with three-and-a-half weeks of running. You can't take shortcuts in the marathon and I guess I learned that today.
"Fingers crossed for 2012. Look at Constantina - how old is she?  Maybe I can do that. I know in London I will have all that support."
Having only confirmed her participation days before the marathon, Radcliffe was determined not to repeat her performance in Athens four years ago where she dropped out after suffering from dehydration.
The Bedford athlete started comfortably enough as she kept pace with the early pace setters.
But she started to tire just after the halfway mark as Tomescu hit the front and stretched the field with a burst that was to see her through to the end.
Radcliffe battled to stay in contention, but she had no response to the breakaway pack and she appeared visibly shattered.
"I would have walked because it was something that was actually ok walking. I haven't made the injury worse.
"If I felt I was doing some serious damage I would have stopped. It's horrible when you have to drop out, especially when it's the Olympic Games. So many people have worked so hard to get me here.
"I wanted to finish. It was really frustrating because I felt really comfortable. I could talk and tell (husband) Gary what was wrong.
"My calf was just so bad I had to stretch it. The pain felt like it was coming up from my foot. Early in the race I had this weird feeling that someone was kicking my foot away while I was running."