Lance Armstrong, in the midst of a much-watched comeback, broke his collarbone Monday in a mass crash during the Vuelta a Castilla y Leon race in Spain and will have surgery.
This was the first time in his career that Armstrong was planning to ride in the world's two most prominent races in the same year.
On Monday, in a Twitter message, the 37-year-old Armstrong said: "Broken clavicle (right) . . . Surgery in a couple of days."
He is expected to fly home this morning.
The seven-time winner of the Tour de France launched his comeback in January with the Tour Down Under in Australia, ending a 3 1/2 -year retirement. The race in Spain was his fourth.
About 30 riders in the main peloton were brought down in the crash in the town of Baltanas. Most got up, but Armstrong remained on the ground until Astana support personnel arrived. He left the race in an ambulance.
In a statement, he said what happened was just bad luck.
"At the end of the race, people started to get a bit excited to win. Everybody wanted to be in the front and a couple of guys crashed in front of me, crossed the wheels and I hit them over the top," Armstrong said. "I have road rash abrasions on the right hip and arm but the big problem is the broken collarbone."
Astana team doctor Pedro Celaya said Armstrong suffered a fracture of the middle third of the right collarbone.
"In 17 years as a pro," Armstrong said, "I've been lucky to avoid one of the most common cycling injuries. The crash has put my upcoming calendar in jeopardy."
Columbia-Highroad team doctor Helge Riepenhof said in a telephone interview that 90% of cyclists who have this injury have surgery to insert a metal plate on the fracture. Riepenhof has been treating Belgian cycling star Kim Kirchen, who fractured his collarbone last month during the Amgen Tour of California.
Kirchen had a plate put in and two weeks later was working on a trainer, Riepenhof said, and was riding on roads within 4 1/2 weeks.
He is scheduled to return to racing March 31.
Via Twitter, Astana team director Johan Bruyneel said Armstrong's fracture was a "clean collarbone fracture." Riepenhof said if that's the case, Armstrong's ability to race in the Tour de France shouldn't be in doubt.
Howard Marans, an orthopedic surgeon in Fountain Valley who once owned a track cycling team and still works frequently with cyclists who have similar injuries, said Armstrong could be back on a training bike in "a few days."
"Last summer I worked with the junior national track cycling team and one of the kids broke his clavicle. We had him back on the bike in five days; he got a bronze medal on Day 10 and on Day 13 he won a gold."
Tour of California winner Levi Leipheimer, who races with Armstrong on the Astana team, said the road where the crash occurred was in bad shape.
"It was very deteriorated and rough and very narrow," he said from his hotel in Spain. "It was just unfortunate the way Lance hit the ground. I think the biggest concern is that Lance will lose a week or two of training. I could be wrong, but I think Lance won't be off the bike very long and will ride in the Giro."
During the 2003 Tour de France, American Tyler Hamilton broke his collarbone but continued racing and won a stage that included a mountain climb. He had suffered the fracture on the second day of the race, July 6, and won his stage July 23.
Scott Nydam, a training partner with Leipheimer in Santa Rosa who races for BMC Racing, also fell and broke his collarbone in a Tour of California crash. It was his second break in seven months, so he had to have the plate that had already been in his shoulder replaced with another.
"I crashed on a Wednesday, had surgery on Friday and was back on the bike in a week," Nydam said. "My fitness took a hit but Lance, he'll have the best doctors. He could race in the Giro for sure. It might not be ideal for winning, but he could use it for training and he could be totally ready for the Tour de France."