Usain Bolt says he is fit and ready for the London Olympics and is convinced his defence of the 100 metres title could trigger one of the fastest ever races in the blue ribbon event.
The 25-year-old Jamaican says he had been training well after a minor hamstring problem and reiterated his desire to become a "legend" of the sport by defending his 100m and 200m titles.
Concerns about the fitness of the biggest name in track and field arose when cameras were banned from his training sessions and he was pictured receiving treatment on his hamstring.
Bolt dismissed those concerns, saying a stiff back causing some problems for his hamstring had been fixed.
Bolt's aura of invincibility was dented earlier this month when he was beaten over both 100m and 200m by training partner and world champion Yohan Blake at the Jamaican trials.
But Bolt says he's been beaten before an Olympics before - Asafa Powell did it in 2008, and says it's a timely wake-up call.