Michael Phelps has become the most successful Olympian of all time after leading his country to victory in the men's 4x200m relay final.
The Baltimore Bullet earned his 15th gold medal when flew through the final leg of the race, leaving behind Yannick Agnel of France in his wake.
Agnel and France took the silver medal with a time 7:02.77, several seconds off the USA's 6:59.70. China secured the bronze with Sun Yang hitting the side at 7:06.30.
Great Britain, led off by Robbie Renwick, finished in an admirable sixth place. Ross Davenport powered through the final length to edge out the South Africans.
Phelps - who won silver in the men's 200m butterfly earlier tonight - now has 15 gold medals, two sliver and two bronze to his name, surpassing the tally of Soviet gymnast Larissa Latynina.
