American sprinter Dalilah Muhammad has broken the world 400m hurdles record at the US Championships.

On Sunday, she clocked 52.20 seconds on the final day of action of the championships to achieve the feat. The Olympic champion was 0.14 seconds faster to Yuliya Pechonkina, who had set the previous world record on August 3, 2003.

Drawn in lane four, the Rio Olympic gold medallist 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.

Unfazed by the rain, the 29-year-old had a clear lead as she entered the final straight with Little, McLaughlin and Ashley Spencer locked in a battle for the runner-up spots. There was no catching Dalilah as she charged through the line in 52.20 seconds.

“My coach kept telling me it was there,” IAAF quoted Dalilah telling NBC after the race. “I just had to trust that and go for it. I wanted it so bad, I knew I had to go out there and prove myself.”

McLaughlin finished second in 52.88, just 0.13 shy of her lifetime best, with Spencer finishing strongly to take third place in 53.11, equalling her previous best.