World marathon record holder Paula Radcliffe admitted on Wednesday that she may never take part in a competitive race again because of ongoing complications with her foot injury.
Radcliffe, who set the women's world record with a time of 2:15.25 during the 2003 London Marathon, was forced to pull out of the 2012 London Olympics shortly before the start after specialist treatment in Germany failed to cure the problem.
The 39-year-old, a gold medallist at the 2005 World Championships and 2002 Commonwealth Games, then underwent surgery in August when it emerged her injury was more serious than first thought.
At that point Radcliffe still retained hopes of participating in a 10-kilometre race, as well as the 2014 London Marathon, but now, with her injury problems persisting, she concedes she may never be able to return to the sport.
"Targets have gone out of the window," Radcliffe told BBC Sport.
"I'm very much in that limbo where I know and accept that realistically it may not be possible.
"But at the same time I have a little window of hope and I would rather be able to finish my career in a race, rather than a race I can't actually get to the start line of."
Radcliffe has endured severe pain in her left foot for 18 years, but despite that she became world marathon champion in 2005 and twice won the world cross-country title.
Next month marks the 10th anniversary of her world record, yet Olympic success has eluded Radcliffe, who finished fourth in the 10,000m in Sydney in 2000.
Despite the frustration of having to withdraw from the London Olympics only days before the marathon, Radcliffe targeted a return at this month's World Cross-Country Championships.
When that became an impossible goal, she aimed for competing in a 10km race, but she now knows her career is dangerously close to an unwanted end.
"I've not even been able to run after the kids in the last few months, and you start to think about the first goal - to get back and be able to have a normal active life and then worry about if I can get back to competing," she said.
"In all honesty with me, it was probably always going to be something going wrong with my body that would make my career start to wind down because I am always going to want to keep competing and keep getting out there.
"I would love to be able to run a couple more marathons before I finish, even if it's just another half marathon.
"At the same time I would still like to have a healthy foot in 20 years' time," she said.