Lauryn Williams stormed to her second gold of the World Championships as she guided home the American quartet in the women's 4x100m relay in Helsinki. Angela Daigle, Muna Lee, Me'Lisa Barber and World 100m champion Williams made no mistakes on their changeovers to cruise home in 41.78 seconds.
World 100m silver medallist Veronica Campbell brought home the silver medal for Jamaica.
Belarus took a surprise bronze as fancied France faded to finish fourth.
Willliams admitted their triumph took on extra significance after the men's sprint relay team crashed out of the heats after dropping the baton.
"The atmosphere was really bad after the men's race on Friday so it was important we came through and raised the morale," said Williams.
"I always hoped for two gold medals the whole way through."