Dalilah Muhammad of the United States stormed to her second world-record run of the season to claim gold in the 400 metres hurdles at the World Athletics Championships.
Muhammad broke Yuliya Pechonkina's record, which stood for almost 16 years, when she won at the US Track and Field Championships in July, clocking 52.20 seconds.
The reigning Olympic champion became the first track athlete to set an all-time best in an individual race at these championships in Doha on Friday, clocking a blistering 52.16 secs.
As expected, Muhammad was pushed all the way by her compatriot Sydney McLaughlin, whose brilliant personal best of 52:23 was the third-quickest in the history of the event – having chased relentlessly from a draw two lanes inside the new world champion.
Jamaica's Rushell Clayton took the bronze, while Muhammad now has a gold to sit alongside her silvers from Moscow 2013 and London 2017.