Usain Bolt says he is still the fastest man in the world as he prepares for the final races of his career at the World Championships in London.
Bolt, an eight-time Olympic champion and icon of world sport, has led one of the most illustrious athletics careers.
The Jamaican, 30, will run the 100m and 4x100m relay at the Worlds, which begin on Friday, before retiring.
"You guys know if I show up for a race that means I'm 100% confident," he said.
"I'm finally here, I've got the hype, I'm really excited and am looking forward to it.
"For some reason I am the underdog again, because that is what I keep reading, what my team keeps telling me, so I have got to prove myself once more.
"But I am ready. It's go time, so let's go."
Listen to Bolt: 100 days that shook the world (19.30 BST, 1 August, BBC Radio 5 live and as a podcast shortly after broadcast)
Watch: The Heroes of Super Saturday
The men's 100m final is on Saturday, 5 August, while the men's 4x100m relay race - which will mark the end of Bolt's career - is on the following Saturday.
Bolt has won the 100m, 200m and 4x100m gold at the past three Olympic Games - Beijing 2008, London 2012 and Rio 2016.
However, his unprecedented 'triple triple' of nine gold medals was downgraded to eight after Jamaican team-mate Nesta Carter, who was part of the quartet that won the 4x100m in Beijing, tested positive for a banned substance. Carter has appealed against the decision.
Nevertheless, Bolt's exploits remain unprecedented and he also holds the world record in the 100m (9.58 seconds) and 200m (19.19).
Asked if he still believes he is the fastest in the world, the Jamaican replied: "Yeah, without a doubt.
"The last race I ran was a 9.95, so that shows I am going in the right direction. After the two rounds leading up to the 100m final, which always help me, it's all about who keeps their nerve.
"I have been here many times. I know I am ready."
