By Rod Gilmour
BUDAPEST (Reuters) - It will be a case of what might have been for Chad Le Clos on Saturday as the South African will have to watch on as a spectator when the 100 metres men's butterfly final takes place.
Instead of going for an expected hat-trick of world championship golds in the event, Le Clos will be a mere bystander when the race takes place after he surprisingly failed to make the finals.
Rising American star Caeleb Dressel blitzed the field in one of the standout performances in Friday's semi-finals, clocking 50.07 seconds and edging closer to Michael Phelps's world record time of 49.82 seconds set at the 2009 championships.
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Le Clos said he had swum "like an idiot" after miscalculating a race plan which saw his bid for the hat-trick thwarted.
"Caeleb was swimming amazingly and I really wanted to race him and the rest of the boys," Le Clos, who missed the cut by finishing 12th overall in the semis, told reporters.
"There's nothing I can do now. I'm pretty much done racing so I'll see what happens."
Yet the South African's championships will be remembered for his 200m butterfly gold on Wednesday.
"Ever since I lost the Olympic final (finishing fourth) this was the main focus," he told a small media gathering earlier.
"I said that I could come eighth and eighth in the 200 free and 100 fly but as long as I won the 200 fly then I would be happy."
Le Clos, whose fortunes have turned since he started training in Turkey, admitted that no one had expected him to land gold.
After a bold opening on Wednesday where he led by half a second at 100m, he held off Hungary's Laszlo Cseh by 0.39 seconds.
The London 2012 champion said: "I was racing myself and I knew that everyone would come at me in the last 50. If I looked around then I would have lost speed."
Last summer, Le Clos announced that both his parents were being treated for cancer. His father, Bert, and mother, Geraldine, were present at the Duna Arena for their son's stirring victory.
"The win was a combination of emotion and team sacrifice," added Le Clos, who was in tears on the medal podium.
Le Clos will watch his friend and rival Cseh in Saturday evening's final, along with 12,000 others.
With Cseh - who qualified sixth for the 100m final - approaching 32, it is not clear how long he will keep competing.
"With respect, if it wasn't for Michael Phelps or Ryan Lochte he would be one of the greats," Le Clos said of Cseh, with whom he said he would meet up for lunch on Monday.
"I'm 25, nearing the prime of my life, and hopefully I can still be that great when I reach his age."
(Editing by Gareth Jones and Pritha Sarkar)