Jeremy Wariner had won the previous two world championships in the open 400 metres, but lost his title a few days earlier.
Warner held the pole, behind Soriano, Ben Offereins was able to sneak Australia into third while Michael Bingham was being challenged by Piotr Klimczak for Poland.
Bingham was able to get around Thomas and then Soriano, putting Great Britain into a solid second place by the straightaway, but Wariner was running away from the pack.
Because of the change in positions, Bingham had to cross in front of several teams to make their exchange, and Kévin Borlée ran Belgium from last to fourth on the straight.
USA had new world champion LaShawn Merritt on the anchor he immediately started widening the gap on Martyn Rooney for Britain.