Missy Franklin has been dubbed America's swimming 'Wonder Woman' after claiming her fourth gold at the world championships by anchoring the US team to victory in Thursday's 4x200m freestyle relay.

Franklin, 18, powered down the pool in the final leg to clock 7 min, 45.14 sec for the US, the Olympic champion, with Australia finishing second 1.94 back and France taking bronze 3.29 adrift.

It was an exact repeat of the medalists in the London 2012 Olympic final.