France swept past the American favourites to win the women's 4x100m relay title at the World Championships.
A devastating anchor leg by Christine Arron sealed gold in a time of 41.78 seconds - the fastest time in the world this year and a new national record.
The Americans, led home by Torri Edwards, took silver while Russia held on to claim the bronze.
"We never thought the Americans were invincible," said Arron.
"I fancied my chances against Edwards on the final leg, provided I got a good handover, and it was better than that.
"This makes up for missing out on the medals in the 100m."
Patricia Girard, European 200m champion Muriel Hurtis and Sylviane Filix stayed with the American team over the first three legs but Arron's final sprint really made the difference.
The European 100m record holder chased down world 100m silver medallist Edwards, eclipsing her in the final metres to snatch gold.
All the talk before the race had been about Kelli White, the American anchor who had been pulled out because of an investigation into a positive drugs test.
But her relay team-mate Chryste Gaines played down suggestions that her absence effectively lost them the title.
"We didn't know why she didn't show up," said Gaines.
"But we had three different ways of running it.
"Of course I am disappointed, every world championship team I've
been on has won gold."
2. United States 41.83
3. Russia 42.66
4. Ukraine 43.07
5. Germany 43.27
6. Belgium 43.45
7. Belarus 43.47