Nye, who won the 71kg at the International Weightlifting Federation (IWF) Junior World Championships, beat her own senior and junior Pan American records in clean and jerk (137kg) and total (246kg).

Her victory, by the week’s biggest margin of 34kg, was a landmark for the United States on two counts.

It was the first time an American male and female had both won world titles in the same year, after CJ Cummings’ victory on Monday, and the first time two Americans had won gold at the same Junior World Championships.

“It was a quick turnaround after the Pan American Championships, but I think it went well, I’m really happy,” said Nye, who had set junior and senior continental records in Guatemala in April.

She did not start until everybody else had finished in both snatch and clean and jerk, and made five of her six lifts.

Had Nye, 20, not missed her second snatch at 108kg she would have tried to beat Sara Ahmed’s junior world record of 111kg.

Ahmed, the Egyptian Olympic medallist, beat Nye into second place at the IWF Junior World Championships in Tashkent, Uzbekistan, last year.

“I really wanted to go for the world record, but we’ve had a pretty good meet all things considered,” said Nye.

The Americans are remarkably strong in this weight class, with three athletes among the top 10 totals made since it was introduced last year – Nye, Mattie Rogers and Meredith Alwine.

Nye, who competed as Kate Vibert until her marriage six months ago, is arguably the most improved lifter in the United States, male or female.

Four years ago, having given up gymnastics, she was keeping in shape through CrossFit, which was how she discovered weightlifting.

When she won a junior medal in December 2015 she realised she might have the talent to compete seriously, so in 2016 she got to work – and her efforts have been remarkable.

When she started, Nye totalled 121kg and now she is way past that in clean and jerk alone, and hopes to match it in the snatch, in which she is stronger.

Nye, who lives near Detroit, has stuck with the same coach, Josh Galloway, and has also spent many hours training alone.

In an interview for Weightlifting House last February she said: “I love weightlifting and always look forward to training because it’s the highlight of my day.

“I have such a passion for the sport.”

The biggest reason for her recent improvement, she said, was a change in body weight.

Under the old weights Nye started at 63kg, which she found very difficult, then moved up to 69kg.

Her totals are up about 50kg since this time two years ago thanks to “an explosion of progress” after going up to 71kg when the weight classes changed last year.

“It was what my body really wanted,” she said.

Now Nye will prepare to go up again, to the Olympic weight class of 76kg.

Having beaten the popular Rogers in Guatemala, Nye has been selected for the Pan American Games in Lima, Peru in July – at 76kg.

The silver medallist was the 17-year-old Russian Evgeniia Gusena (212), with Turkey’s Berfin Altun (206) third.

Phil Andrews, chief executive of USA Weightlifting, said, “Kate’s explosion in this quad has been quite remarkable to watch.

“She, and her coach Josh, have an outstanding positive mindset.

“We are exceptionally proud of Kate’s achievements in Fiji and are looking forward to seeing what happens at the Senior Worlds later this year.

“Quite incredible progress, quite incredible lifting.”

Egypt won both the other events of the day, the women’s 76kg and men’s 96kg.

Rania Mahmoud, a 17-year-old who has won multiple continental titles at youth, junior and senior level, won the 76kg on 219kg, well below Nye’s total at a lower weight.

Youth world champion Dilara Narin, of Turkey, missed two clean and jerks and finished second, 2kg behind.

New Zealand’s Kanah Andrews-Nahu, who was fourth behind silver medallist Narin at +63kg in the Youth Olympic Games in Buenos Aires last year, won the snatch on 98kg and finished third on total – one place ahead of the American Athena Schrijver, who took clean and jerk bronze.

Andrews-Nahu, 18, one of New Zealand’s best prospects in years, made a career-best total of 212kg, 1kg more than she lifted in Buenos Aires, where she weighed 7kg more.

Russia won another bronze in the men’s 96kg, in which the 16-year-old Artur Babayan made 346kg to finish third, an effort that would easily have won gold at the IWF Youth World Championships this year had he competed.

The Egyptian Ahmed Ali, second last year, took gold with 365kg, ahead of Artyom Antropov of Kazakhstan on 352kg.