Jamaica upset Olympic champions United States to win the world women's 4x400 metres relay final here on Sunday.
Novlene Williams-Mills overtook Francena McCorory with 10 metres to go as the Jamaicans clocked three minutes, 19.13 seconds, the world-best time this year, beating their rivals by 0.31 seconds.
Britain took bronze in 3:23.62 minutes at the Bird's Nest stadium.
