USA disqualified, France win men's medley relay
France's Camille Lacourt (L) and France's Giacomo Perez-Dortona (R) celebrate after winning the final of the men's 4x100-metre medley relay swimming event in the FINA World Championships at Palau Sant Jordi in Barcelona on August 4, 2013.
Although Nathan Adrian of the USA touched the wall first in the anchor leg, judges ruled Cordes had dived off his blocks before the first change over, which saw the defending champions disqualified.
"I don't blame him, he's a rookie, he'll be there next time," Adrian said after Cordes' error.
The French quartet clocked an official time of 3min 31.51sec with Australia at 0.13 back and Japan at 0.75 adrift.
While the Americans were left distraught, the French were elated at their victory, their second relay title in Barcelona's Palau Sant Jordi pool after winning the men's 4x100m freestyle final last Sunday.
This was the first time the American men's team failed to win the medley relay at a world championships since 2007.
Camille Lacourt, who claimed his second gold of the night after earlier winning the 50m backstroke, described France's victory as a "magic" moment.
"Tonight is gonna be crazy, sessions like this is one of the reasons why I love this sport so much," beamed Lacourt.
"Swimming with my friends and winning two golds in front of such a great audience makes my life complete.
"I will remember this day, it's really magic."
Jeremy Stravius, who swam the third leg, said the gold was not undeserved.
"The Americans played with fire and it was a mistake on their behalf which made us world champions, but it was not an undeserved win," said Stravius, who had earlier won silver in the backstroke.
"I knew we had a shot at the medal after seeing the first two legs unfold."