Lars Bak will miss the start of the spring Classics campaign after breaking his wrist in a crash during the GP Cycliste la Marseillaise on Sunday.
The 33-year-old Dane, who rides for Lotto-Belisol, fractured his scaphoid in the first race of the European season and will now undergo surgery to fit a small screw into the bone.
He will be off the bike for a week and is not expected to be back to full fitness in time for Omloop Het Nieuwsblad on February 23 or Kuurne-Brussels-Kuurne on February 24.
However, it is hoped he will be ready for the remaining Classics, as well as Paris-Nice, which takes place from March 3-10.
Jonas Van Genechten will replace Bak for Lotto-Belisol in the five-day Etoile de Bessèges, which starts on Wednesday.
The GP Cycliste la Marseillaise was won by Justin Jules (La Pomme Marseille). The Frenchman defeated Samuel Dumoulin (Ag2r-La Mondiale) in a sprint finish, with Thomas Damuseau (Argos-Shimano) crossing the line third.