Belgian rider Michael Goolaerts has died of cardiac arrest after collapsing while competing in the Paris-Roubaix one-day classic.
Goolaerts' team said the 23-year-old died in a Lille hospital where he had been taken by helicopter on Sunday.
"It is with unimaginable sadness that we have to communicate the passing of our rider and friend Michael Goolaerts," the Veranda's Willems-Crelan team said in a statement.
The team said Goolaerts died "in the presence of his family members and loved ones, who we keep in our thoughts."
It added that he "died of cardiac arrest, all medical assistance was to no avail."
TV footage of the 257km race showed Goolaerts lying unresponsive on the side of the road as the peloton passed him.
He was quickly attended by a medical team and appeared to receive CPR.
David Lappartient, president of the Union Cycliste Internationale, expressed the organisation's sadness at the tragic news.
"On behalf of the International Cycling Union and the cycling family as a whole, I would like to extend my deepest condolences to the family, team and loved ones of Michael Goolaerts, who left too early today. We share their immense sadness," he posted on Twitter.
Goolaerts rode in support of cyclo-cross world champion Wout van Aert of Belgium in the race dubbed the "Hell of the North" because of the difficult terrain it covers.
Goolaerts finished ninth in the Dwars door West-Vlaanderen one-day race last month and was 20th at Kuurne-Brussels-Kuurne earlier this season.
