Paralympic athlete Danny Crates remains confident he will be fit to defend his T46 800m title in Beijing in September.
The 35-year-old Briton has been struggling for much of the year with a series of Achilles tendon problems.
"It has been tough as the Games get closer but I'm still very positive," he told BBC Sport.
"I've been lucky with injuries over the course of my career and it is just unfortunate that this has happened in a Paralympic year.
Crates, who lost his right arm in a car accident in Australia in 1994, is the current world and Paralympic champion in the event.
He suffered a small tear in his back and another in his calf in March and a series of injections has failed to completely cure the problem.
"There aren't many athletes who get to the end of a season without some sort of niggle," he said. "But this is the Paralympics and it is what I have worked for over the last four years.
"Earlier this year, Beijing was all about defending my title but now it is all about getting to the start line in a strong and fit state to defend the title.
"The situation has been very frustrating over the past couple of months but I believe that there is now light at the end of the tunnel.
"I always said I wouldn't go to Beijing if I didn't have the potential to win but you don't know until you go and some people do amazing things at Olympics and Paralympics and I hope I can join that list."
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