Roubaix (AFP)
Grondin (21) won the sprint in this 60-lap (15 km) long race which is not on the Olympic program.
Bronze medalist at the Tokyo Olympics with Benjamin Thomas in the American race, the Frenchman beat the Belgian Tuur Dens and the Briton Rhys Britton.
"It had been a while since I had scratched," said the winner.
"You never know what's going to happen, it's random. In the last lap, I had in mind not to crack, to give everything and I succeeded. I had a good feeling at the end , it was unlocked. "
"I was carried by the public, I had my parents who made the trip," added the new world champion.
Gurnard, who wears the colors of the Arkea-Samsic team on the road, took over from Yauheni Karaliok (Belarus).
"I still have two events, the omnium and the elimination, we will see what it will give", concluded the French, junior world champion of the omnium in 2018.
© 2021 AFP