Classics specialist Alessandro Ballan is facing a prolonged period off the bike after breaking his leg, injuring his spleen and puncturing a lung in a high-speed training accident in Spain.
The 33-year-old Italian has already undergone one emergency operation to remove his spleen, but will need another to repair a displaced fracture of his left femur.
The BMC rider was descending the Coll de Rates climb, close to Parcent, near Valencia, at the end of a four-hour ride on Thursday when he crashed.
The impact also broke a rib, which consequently caused a small puncture of a lung.
Ballan had been scheduled to race at the season-opening Tour Down Under next month, before embarking on a spring Classics campaign.
The 2008 world road race champion was looking to improve on his performance in 2012, when he finished third in Paris-Roubaix and the Tour of Flanders, and fourth at Strade Bianchi.
BMC Racing Team directeur sportif John Lelangue was unable to put a timescale on Ballan's recovery.
He said: "Of course, his loss means a lot since Alessandro is one of our key riders for the classics.
"But most important right now is that he can recover and just get back to his normal process.
"We will wait for all the medical information before even beginning to think about what could be his plan for coming back."