LONDON (Reuters) - Reinvigorated after winning the 200 meters individual medley gold medal on Thursday, Michael Phelps dived straight back into the London Olympic pool and booked a place in Friday's 100 butterfly final, his last individual event before he retires.
Showing no signs of fatigue despite his busy schedule and advancing years, the 27-year-old easily won his semi-final in 50.86 seconds.
The race took place less than an hour after the medley final but Phelps was able to catch his breath and qualify fastest for the final.
"He does that better than anyone, doing the second event after the first really hard one," said his coach Bob Bowman.
Phelps won the 100 butterfly gold at the last two Olympics but faces a stiff challenge making it three on the trot.
The finalists include Serbia's Milorad Cavic, who Phelps famously beat by a fingernail in Beijing to win the seventh of his eight golds in China.
Phelps will also take on South Africa's Chad le Clos, who has surfaced as his biggest danger after Le Clos beat the American in the 200 final and qualified second fastest for the 100 but he said he did not think he could win the shorter race.
"In tonight's 100m fly (semi-finals) he was a bit tired and made a great time so I think tomorrow night will be a little bit unrealistic to try and win," le Clos said.
"I'm next to him again so that will be another dream for me to swim next to Michael Phelps."
(Reporting by Julian Linden; Editing by Greg Stutchbury)
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