Italy's Alessandro Ballan has had surgery to have his spleen removed following a training crash.
The BMC Racing rider was also left with a broken leg and rib following the collision in Eastern Spain.
"The broken rib actually made a small puncture in his lung," said the team's chief medical officer Max Testa. "The first priority is the spleen injury - that is considered a medical emergency."
Ballan, who won the one-day Giro della Toscana in Italy, was training for the season-opening Tour Down Under in Australia when the incident occurred.
"His loss means a lot since Alessandro is one of our key riders for the classics," said BMC team sporting director John Lelangue. "But most important right now is that he can recover and just get back to his normal process.
"We'll wait for all the medical information before even beginning to think about what could be his plan for coming back."
A decision on when to operate on Ballan's leg will be made at a later date.
