Chad le Clos has labelled a "disgraceful" fourth-place finish in defence of his 200m butterfly title at Rio 2016 final as the worst performance of his career.
Le Clos pipped pool icon Michael Phelps in the event four years ago, but a hotly anticipated showdown between them fizzled out in Brazil as Phelps dominated this time around.
The South African now sets his sights on going one better than his silver medal in the 100m butterfly in London, and is confident that he is fit enough to bounce back.
"I don't know what to say. I am in good shape, there is no reason for me to swim that slow," he said.
"I said before I started, there is a possibility I could come in and get two golds, two silvers, two fourths. I stand by what I said. I am in the best shape of my life, so no excuses, we have to do better. We have to do a lot better.
"It's the worst performance of my career. There will never be another worse performance in that event, doesn't matter what I have to do.
"But like my dad said, 'We don't cry for losing, we cry for winning'. As much as I wanted to cry - I really did, I must be honest - I didn't. I said to myself, 'Worse things have happened to me this year'. This is not even the fifth worst thing that's happened to me in the last few months.
"In my mind I was winning. I was so winning. Ten metres to go, I was winning and then my body just wasn't going. What's going on? It was the first time in my life that it was like this.
"I wanted to just race in the final. If I come second and my best time, c'est la vie, nothing you can do, but to lose on the 1:54.0 is disgraceful from my side. I'm not the kind of guy that accepts defeat like this on this kind of level."
Despite his struggles in the 200m butterfly final, Le Clos has already picked up a silver medal - in the 200m freestyle - at the Rio Games.