Sydney McLaughlin-Levrone broke the women's 400 metres hurdles world record for the fifth time on Sunday after crossing the line in 50.65 seconds at the US Olympic trials in Eugene, Oregon.
The 24-year-old Olympic champion improved on her previous mark of 50.68 set two years ago at the same Hayward Field track and will travel to Paris to defend her title.
McLaughlin-Levrone was in a state of disbelief after posting such a quick time.
"I'm just amazed, baffled and in shock," she said.
Anna Cockrell (52.64) was second while Jasmine Jones (52.77) took third.
McLaughlin-Levrone exploded out of the blocks and took the lead immediately, gliding over each hurdle in a technically flawless performance.
Cockrell and Jones were left to battle for the last two spots on the podium as McLaughlin-Levrone was all on her own around the final turn.
She was nearly two seconds clear of the rest of the field as she crossed the finish to thunderous applause from the crowd at the heart of American track.
McLaughlin-Levrone had only run in the event once this season before the US trials but showed no signs of rust as she jogged through the finish of her semifinal in a world leading time.
The only woman ever to run faster than 51 seconds in the event, she will bid to become the first woman to win back-to-back Olympic 400 hurdles titles in Paris.
