USA's McLaughlin smashes global record at World Championships

World record breaker Sydney McLaughlin has warned that "the sky's the limit" after smashing her 400 metre hurdles record, but then hinted that she could well switch disciplines.

The American clocked an astonishing 50.68 seconds for gold at Hayward Field on Friday, obliterating her own world record by more than half a second.

But questions were immediately posed about a potential switch, with McLaughlin insisting all would come down to what plan her renowned coach Bobby Kersee might hatch.

"Bobby and I have talked about possibly looking at other events," McLaughlin admitted.

"But I don't know if that's going to happen. I think we're going to just figure it out at the end of the season ... if we want to switch events or stay with the 400m hurdles."

Asked whether a switch might be to the 400 metres flat, McLaughlin said: "I think anything's possible... but I leave it in the hands of my coach, Bobby.

"My coach thinks there's a lot more to be done," she said. "The sky's the limit for sure."

READ MORE: USA's McLaughlin shatters world record in women's 400m hurdles at Olympics

Flow state reached

McLaughlin, who also won Olympic gold last year in Tokyo in a then-world record, said she hit a type of 'flow state' in the race.

"Just putting everything that you've done in practice into the race to the point where you're like just letting your body do what it does," she said.

"But I think there's always a way to improve upon. I think we're pushing the boundaries as a sport, especially in our event of what's possible in this race. So I definitely think there's always more time that can be shaved off, for sure."

McLaughlin said she loved competing on the "big-stage race knowing that the crowd was full and I had really great women that I'm racing against".

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