The best-laid plans of the world’s top racers were blown apart in the chaos of the cobbled streets of Montmartre, as Kristen Faulkner of the USA team emerged to claim the gold medal in the women’s Olympic road race.

On a day littered with tactical confusion, the absence of race radios only fuelled the sense of mayhem. It needed a cool head to assess the possibilities for victory, and when it came to the pivotal moment, just under three kilometres from the Trocadéro, it was Faulkner who had it.

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Behind her the London 2012 gold medallist, Marianne Vos of the Netherlands, and Belgium’s Lotte Kopecky, the current world road race champion, rued the tactical stalemate that allowed the American to slip clear.

Vos and Kopecky were far from alone in that feeling: Team GB’s riders were also left to ponder what might have been as a potentially race-winning scenario evaporated and left them finishing out of the medals, although Pfeiffer Georgi ended up a creditable fifth.

With only three nations – Belgium, the Netherlands and Italy – starting with a full quota of four competitors, the 92-rider race proved even more uncontrolled than the men’s event on Saturday.

Team GB’s original four-rider lineup had been reduced to three even before the start, with Anna Morris dropping out to focus on the track racing programme, which begins on Monday. That left Anna Henderson, silver medallist in the women’s time trial a week ago, the London 2012 silver medallist Lizzie Deignan and Georgi, the British national champion, pursuing GB hopes in the 158km race.

As in the men’s race, an opportunistic break moved clear in the early stages, but it was on the Côte du Pavé des Gardes, 90km from the finish, that the first serious attacks materialised. Further accelerations put paid to the early breakaways and the main favourites arrived together, at the finishing circuit, on the Côte de la butte de Montmartre. At the foot of the first ascent to the Sacré Coeur, a crash delayed Faulkner’s United States teammate Chloé Dygert and also held up Kopecky.

That proved the catalyst for a select group, that included all three British riders, to move clear. With Kopecky distanced and other contenders also cut adrift, the trio were suddenly in pole position. But that situation was short-lived. In the absence of information, the GB team seemed uncertain on the best tactics and, in fact, ended up unwittingly attacking each other.

Meanwhile Kopecky, who will race this week in the omnium in the Olympic velodrome, finally recaptured the front of the race. “I had to go all in to get myself in contention again,” she said.

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With 22km remaining, Vos and Hungary’s Blanka Vas followed Deignan in a sudden attack, but then left her behind as the road rose towards Montmartre once more. From there, Vos and Vas were on their own, seemingly bound for the podium, until Kopecky, working with Faulkner, set off in pursuit on the last of three climbs to the Sacré Coeur.

That final climb on Montmartre was also a hill too far for the British trio, with Henderson and Deignan definitively falling back, and Georgi unable to follow Kopecky’s brutal acceleration. “I was really hoping something special might happen and that I’d be in the shout for a medal,” Georgi said. “But the last time up the climb, my legs said ‘No’. I just saw them riding away, which hurts a bit.”

Deignan acknowledged her attacks had sparked the decisive move, from Vos and Vas. “I like being part of the game,” she said. “I love the game.”

The former world champion tested positive for Covid during the Giro Donne in July and was in hospital 10 days before the road race, with a medical emergency. “I had an absolutely abysmal preparation for this race,” Deignan, who finished 12th, one place ahead of Henderson, said. “I knew I had good shape, but I knew there was no final in the legs. I knew that last 120km I’d be struggling. It’s been one of those buildups. It’s been an emotional rollercoaster and I’m ready to chill out now.”

Georgi’s fifth place finish left her frustrated. “I’m a little bit gutted,” the British national champion said. “There’s always things to improve. We could have done a few things different, but the Olympics is a completely different dynamic to any other race.”

Faulkner, meanwhile, who will ride this week in the women’s team pursuit, wholly deserved her success. Selfless in pursuit of Vos and Vas as they closed on the finish line, she received minimal support in the chase from Kopecky, who was content to sit in her slipstream.

When, 3.5km from the finish, the quartet finally came together, the American did not hesitate. As Vos, Vas and Kopecky dallied, Faulkner, knowing she would be the poorest relation in a sprint finish, immediately counterattacked to take gold. “It was my moment and I knew I had to take it,” she said.