Eugene: Jamaica fielded the three medallists from the women's 100 metres in Saturday's World Championships sprint relay but that was still not enough to prevent a super-slick U.S. quartet taking gold to raise the biggest cheer of the week at Hayward Field.
Jamaica looked formidable after bringing in their "big three" - Shericka Jackson, Shelly-Ann Fraser-Pryce and Elaine Thompson-Herah - with lead runner Kemba Nelson the only survivor from their semi-final team.
The United States introduced Abby Steiner to join Melissa Jefferson, Jenna Prandini and Twanisha Terry, and after a superb series Terry ran a terrific anchor leg to bring them home in 41.14 seconds - the fifth-fastest in history.
Jamaica were second in 41.18 - the sixth-best ever - after losing fractions on a couple of stretched changeovers. Britain were in the medal hunt until 200m bronze medallist Dina Asher-Smith pulled up injured at the end of her third leg, allowing Germany to storm through for a surprise bronze in 42.03.
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