World champion Julian Alaphilippe is in a stable condition after crashing heavily during the Liege-Bastogne-Liege Monument classic but will need to be kept in hospital for observation, his Quick-Step Alpha Vinyl team said on Sunday.
The team said he suffered two broken ribs, a broken scapula (shoulder blade) and a collapsed lung.
The Frenchman was conscious while being treated in an ambulance, TV channel France 3 reported, after the 29-year-old was involved in a huge pile-up near the front of the main bunch and fell into a ditch, around 62 kilometres from the finish.
Team-mate Ilan Van Wilder, 21, suffered a broken jaw in the same accident.
"Both will travel by ambulance to (the city of) Herentals for further examination and treatment," the team said.
