The U.S., who
finished as runners-up in the 4x400m two years ago after four
successive world titles, were anchored by Natasha Hastings and
finished 20 meters ahead of the British team, in a world leading
time of 3 minutes and 21.66 seconds.
Britain's quartet qualified in 3:24.74, with Botswana clinching
the third automatic place in the first heat to make it through
to Sunday's final.
There was heartbreak in the second heat for the Bahamas, running
without Olympic 400m champion Shaunae Miller Uibo, as Christine
Amertil stumbled and fell 200 meters into her second leg. The
team did not finish the race.
The heat was won by Jamaica in 3:23.64, with Nigeria and Germany
coming second and third.
Poland and France also qualified for the final as the fastest
(Reporting by Christian Radnedge; Editing by Toby Davis)
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