The 27-year-old won the 18th and 19th Olympic medals of his career to pass Russian gymnast Larisa Latynina?s tally of 18, which had stood since 1964.
The evening began with Phelps winning silver in the 200m butterfly before claiming gold in the 4x200m freestyle relay alongside USA team-mates Ricky Berens, David Walters and Ryan Lochte.
?It’s very special,? said Phelps afterwards. ?There are still other races and that is what is on my mind right now. I am going to attempt to sleep. I am not sure if it is going to be possible.”
Phelps had looked set to win the 200m butterfly for the third successive Games, but was beaten to the wall in the closing stages by South Africa?s Youth Olympic champion Chad le Clos, who finished strongly to pip the American by just five hundredths of a second.
After anchoring the USA to gold in the relay, however, Phelps ensured that his name was etched into the record books once again, having won more Olympic medals than any other athlete in history., with
IOC President Jacques Rogge praising praised the American?s accomplishments: ?To take part in an Olympic Games is an achievement for any athlete – to win a medal makes you a member of an elite band; but Michael Phelps has made Olympic history tonight by winning his 19th medal and I salute his unique achievement. He breaks the record of Russian gymnast Larisa Latynina and in doing so he joins a group of athletes who have continued to strive for excellence in sport.?
Phelps made his Olympic debut as a 15-year-old at the Sydney 2000 Games and won his first medals four years later in Athens, when he won scooped an incredible six gold medals and two bronzes.
The American broke another recordsurpassed that achievement in Beijing in 2008, however, when he broke surpassed compatriot Mark Spitz?s record achievement of gaining of seven golds at a single Games by winning all eight events that he entered, breaking seven world records in the process.