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Michael Phelps won the 100m butterfly by the narrowest of margins to equal Mark Spitz's record haul of seven gold medals at an Olympic Games, set in Munich in 1972.
Phelps trailed Serbian swimmer Milorad Cavic for the whole race and was well behind with just 15m to go, but he finished like a train to prevail by just 0.01 seconds.
There was no world record this time, but the American set a new Olympic record, touching in 50.58 secs with Australia's Andrew Lauterstein finishing third. World record holder Ian Crocker finished fourth.
Phelps will go for a record eighth gold in the 4x100m medley relay at the Water Cube on Sunday.
Motivation
"Beforehand, Bob (Bowman, Phelps' coach) said it would be good for me if I lost," said Phelps.
"When he said that I was fired up. I said 'I'm going to go for it' and when I saw that finish I said 'wow'. I had no idea the race was that close.
"When I took that last stroke I thought I had lost the race there, but it turns out that was the difference. I'm just lost for words."
Controversy
Controversy followed the race after Serbia lodged a protest over the result at the Water Cube.
Video footage on who touched first proved inconclusive, with some angles even suggesting Phelps was not ahead at the wall.
Serbia lodged a written protest but after officials reviewed footage and the electronic timing systems they declared themselves satisfied with the result.
The Serbs, according to an official, were also placated having had the opportunity to access the same information available to the referee.











