Get real time updates directly on you device, subscribe now.
American Dalilah Muhammad broke the 400m hurdles world record on the final day of the US National Championships in Iowa.
Drawn in lane four, she went out hard and quickly made up the stagger on the athletes outside her, including 2015 world silver medallist Shamier Little and world U20 record-holder Sydney McLaughlin.
The 29-year-old clocked a time of 52.20, shaving 0.14 seconds off Yuliya Pechonkina’s record that had stood since 2003.
