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Michael Phelps wins a record eight gold medals in a single Olympics (2008)
Phelps did the seemingly impossible in Beijing: He won eight gold medals in nine days. They didn't all come easily — there were close calls in two races, including the 100-meter butterfly, in which he beat Serbia's Milorad Cavic by one-hundredth of a second. But when all was said and done in the 4x100-meter medley relay (a race the U.S. men's team has never lost at the Olympics), Phelps surpassed fellow swimmer Mark Spitz's seven-medal haul from 1972 to become the most decorated athlete at a single Olympics. Combined with his medals from Athens (six gold, two bronze), Phelps holds the all-time record for most golds with 14 and is three medals shy of eclipsing Soviet gymnast Larisa Latynina for the all-time total medal record.