Belgian Lotte Kopecky continued an impressive season overshadowed by the death of her brother by winning the first stage of the 2023 Tour de France Femmes on Sunday in Clermont-Ferrand.

Hours before Denmark's Jonas Vingegaard was due to be crowned men's champion on the Champs-Elysees in Paris, SD Worx rider Kopecky crossed the line alone, 41 seconds ahead of her Dutch teammate Lorena Wiebes.

Race favorites Annemiek Van Vleuten and Demi Vollering, both also from the Netherlands, were among the leading group.

"My role doesn't change," said Kopecky, 24, who claimed her 10th win of the season. "I'm here to help Demi win the Tour, and if I have to sacrifice myself, I will." 

The Belgian rider has raced this season mourning the death of her 29-year-old brother Seppe, who died suddenly in March.

On Sunday, she attacked shortly before the summit of the Durtol, nine kilometers from the line, to seal victory.

As well as taking the leader's yellow jersey, Kopecky gets the green points classification and polka dot jerseys for the best climber.

"I had been thinking about this success for a long time," she said. "Sport is above all emotion. And this one is a beautiful one.

"It's a huge success, maybe not the most important because the Tour of Flanders and my track world titles also matter a lot. But this yellow jersey is really big."

If Kopecky "hopes to keep the jersey for a few days," she "does not forget" that she is on the Tour "with a single objective" to ensure that Vollering, second last year behind van Vleuten, wins the title.

"If I have to sacrifice my jersey in the coming days, I will do it," she added.

France's Juliette Labous, runner-up in this year's Giro d'Italia, was the main loser of the day, left behind in the Durtol ascent.

Monday's second stage takes the peloton from Clermont-Ferrand to Mauriac in Cantal, on a 151-kilometer route with six climbs, the last less than two kilometers from the line.