Julien Alfred made history as St Lucia’s first ever Olympic medallist by beating the US world champion Sha’carri Richardson to take gold in the women’s 100m in Paris, as Team GB clocked up its first medal on the track.

Under teeming rain in the Stade de France, the 23-year-old dominated the final and set a new national record of 10.72 seconds, leaving Richardson in silver and Melissa Jefferson, also of the US, to take bronze after a photo-finish with Team GB’s Daryll Neita in fourth.

Neita, 27, said: “It’s super tough – words can’t describe how I’m feeling right now. I was so close to that medal I was dreaming of for my whole life.”

No athlete from the Caribbean island of St Lucia, population 179,000, had ever won an Olympic medal before.

Alfred’s time made her the eighth fastest woman in history on her first appearance at a Games.

Earlier, Sam Reardon, Amber Anning, Laviai Nielsen and Alex Haydock-Wilson had claimed a first track medal for Team GB in Paris after holding on to win bronze in a tight 4x400m mixed relay that was won by the Netherlands on the home straight.

Reardon, 20, from Beckenham, said: “I think we all executed the gameplan perfectly and to come away with a bronze medal, I can’t really believe it.

“It was electric. When I went out to do my block set-up, the French were really hyping up the crowd, so I fed on that energy and it carried me through. It’s a once-in-a-lifetime experience. I went out there and did what I know I can do. I had that belief.”

It followed a Team GB gold in a blue-riband event of the Olympic regatta – the men’s eight – and a dazzling performance by sprinter Louie Hinchliffe who beat the world’s fastest man in the 100m heats, raising expectations of further success.

With medals in rowing, dressage, gymnastics and sailing, Britain had for a brief period on Saturday been ahead of the US in the Olympic medal table, something that has not been achieved at the end of any Games in which both nations have competed since 1908 in London.

An imperious display by Simone Biles, 27, in the women’s vault in the Bercy Arena put that to bed as the US gymnastics superstar notched up her third gold of the Games. Brazil’s Rebeca Andrade took silver and Biles’s teammate Jade Carey finished with bronze.

With three golds in five days, Biles’s overall Olympic medal count now stands at 10, including seven golds, with the finals of the balance beam and the floor exercise to come on Sunday and Monday, respectively.

“I love that the athletes push me to be my best,” she said.

Ryan Crouser, representing the US, became the first man to “three-peat” in the shot put by taking gold ahead of his compatriot Joe Kovacs and Jamaica’s Rajindra Campbell in bronze.

The British team remain on track to hit the upper end of UK Sport’s prediction of between 50 and 70 medals after the best first week of a Games in modern history.

The ambition of the British team was exemplified by the peformance of Hinchliffe in the first round of the 100m where he beat American star Noah Lyles, the world No 1, with a time of 9.98sec.

Asked whether he had been surprised by Hinchliffe, Lyles responded: “Yes and no. He is a talented kid.”

“It was a good feeling,” said Hinchliffe, 22, from Sheffield. “I wasn’t really thinking too much about him, he wasn’t really near me. I didn’t really think about who else was in the race. He said ‘well done’ and acknowledged me at the end.”

The eight day of the Games had begun with the cox in the British men’s eight, Harry Brightmore, leaping on to the stern of his boat to issue a roar of triumph after a perfectly paced race that allowed them to put down the hammer in the final stretch and ease ahead of the Netherlands’ crew.

In the past 100 years, the British eight had only won gold in 2016 and 2000. The win left Britain with eight rowing medals – the most of any nation – although the Dutch topped that table with four golds to the Britons’ three.

Charlie Elwes, 27, from Andover, who won bronze in the men’s eight in Tokyo, said: “I’d say 99.9% of it was perfect.”

Rory Gibbs, another of the world-beating eight, had to seek medical assistance after a heroic push in the last 850 metres while Morgan Bolding was helped from the boat.

Elwes, Gibbs, Bolding, Jacob Dawson, Sholto Carnegie and James Rudkin, Tom Digby and Tom Ford had competed straight after the women’s eight took bronze in a boat coxed by Henry Fieldman, who had coxed the men’s eight to their bronze in Tokyo.

“It was quite breathless, actually,” said Annie Campbell-Orde, 28, from Wells, of the women’s win.

Louise Kingsley, the director of performance for the GB rowing team, said the performances had drawn a line over the nadir of Tokyo in 2021 when the rowing team failed to win a single gold and only collected a silver and bronze.

She said: “An absolutely fantastic regatta, it’s good to be back from Tokyo.”

Britain’s Carl Hester, Charlotte Fry and Becky Moody won bronze in the dressage team Grand Prix Special in defiance of the pressure that came with a ban handed to star rider Charlotte Dujardin on the eve of the Games.

Hester, a mentor to Dujardin who left the Games after the publication of a video showing her repeatedly whipping a student’s horse, said: “It has been really difficult, very hard, and as I said before, we’ve had to put it out of our minds.”

Gymnast Jake Jarman also took bronze in the men’s floor, just behind silver medallist Artem Dolgopyat of Israel. Carlos Edriel Yulo of the Philippines took the gold.

Jarman, 22, from Peterborough, said: “I said to myself: just do the best you can. Especially after seeing there were two ridiculously high scores up first. I knew it was going to be insanely hard. I just wanted to enjoy it, do the best I can.”

Emma Wilson, 25, a favourite for gold in the sailing, was unhappy with her bronze medal off the coast of Marseille after a new winner-takes-all section at the end of the competition.

She said: “It’s not OK to put people in this position every time. I had a 60-point lead at the world championships, and a 30-point lead here.I don’t know how many times you can come back. I think I’m done with the sport.”

Team GB boxer Lewis Richardson is through to the Olympic semi-finals and guaranteed at least a bronze medal after beating Zeyad Eashash of Jordan by split decision 3-2 in the men’s 71kg category. The golf enters its final round on Sunday, with Tommy Fleetwood, from Southport, one shot off the lead in third position.