French cycling star Julian Alaphilippe will miss the upcoming Ardennes classics with a right knee injury, his Quick-Step team announced on Tuesday.
The 24-year-old has been struggling with the injury since falling in last week's Tour of the Basque Country.
Alaphilippe, a stage winner in the recent Paris-Nice who came third at last month's Milan-SanRemo, was among the favourites for Sunday's Amstel Gold Race.
He was also expected to feature strongly at the Fleche Wallonne, where he came second in 2015 and 2016, and at Liège-Bastogne-Liège, in which he was the runner-up in 2015.
The Frenchman will undergo tests in the coming days to determine exactly how long he faces out, his team added.