Usain Bolt set his sights on breaking his 200 metres world record at the Rio Olympics after declaring himself fit and ready to race following a visit to his controversial German doctor.
The six-time Olympic champion faces a key test of his fitness when he races for the first time since pulling out of the Jamaican trials with a hamstring strain - and the first time over 200m all season - at the Muller Anniversary Games in London on Friday night.
"I went to see the doctor to work his magic as always, I'm good," the 29-year-old told a packed press conference.
"My hamstrings are good, I have no issues right now. The doctor did an extremely good job. I know I'm in good shape."
Bolt's doctor is the renowned Hans-Wilhelm Muller-Wohlfahrt, the 73-year-old Germany national team doctor known as 'Healing Hans'. He has treated a host of the world's leading sports stars, but whose unorthodox methods - including his use of homeopathy and calves' blood injections - divide opinion.
The Jamaican, who also gave his backing to the decision to ban Russia's athletes from the Games and was sporting a plaster on his left arm following a drug test of his own on Thursday morning, visited Muller-Wohlfahrtin Marseille, where he was with the Germany squad at Euro 2016, a fortnight ago.
He said: "I've been going there for years. I have a really bad back problem and every year it gets worse.
"He's the only person I've been to over the years that has figured out a way to make sure my back is okay and I can compete and I can stay on track.
"I'm tested all the time, years upon years. I got tested this morning. The IAAF (athletics' world governing body) test me all the time, WADA (the World Anti-Doping Agency) test me, everybody tests me.
"I have all the trust in my doctor and I support him 100 per cent."
Bolt's outing at the Olympic Stadium, the scene of his three Olympic gold medal wins at London 2012 in the 100m, 200m and sprint relay, will be his last before the Rio Games, where he will bid for an unprecedented 'triple triple' of Olympic crowns.
His absence from Rio would have been a hammer blow to the event - it is difficult to imagine a star has ever been more important to his sport than Bolt is to athletics, especially in the current climate.
He insisted, however, he was "never really worried" his hopes of competing in Brazil might be in danger, despite admitting he would probably have torn his hamstring "really badly" had he competed at the trials.
"I'll definitely be there," he said. "This is where history is going to be made. I'm looking forward to going down there and doing my best and putting on a show for the whole world to see."
And that show, he believes, could include breaking his 200m world record of 19.19 seconds, set back in 2009 at the World Championships in Berlin.
Bolt said: "I'm happy that I didn't get a really bad setback this season, it was up and down, but I could always train.
"I think the competition, the energy, the work they have to put in to win the 100m in Rio will help my 200m and that's really my focus, trying to break the 200m world record."
Based on his times over recent seasons that is a feat that looks some way off - his fastest time since has been 19.32 at the London Olympics.
However Bolt is familiar with defying the doubters, especially last year when he went into the World Championships in Beijing trailing two-time convicted drug cheat Justin Gatlin in the 100m and 200m world rankings only to leave China with the complete set of gold medals.
"I think I'm definitely a tough competitor, mentally," he said ahead of another showdown with the controversial American in Rio.
"Last year Gatlin was just not ready. It was the first time he was actually being chased. He had a tough competitor which was me. It was hard for him.
"This year is not going to be the same, I'm in much better shape, so I won't leave it to the last second."
