Defending Olympic champion Samuel Sanchez withdrew from the Tour de France after a crash during the eight stage in which he sustained injuries that could rule him out of the London Games.
Sanchez was involved in a spectacular crash that occurred 56 kilometers (35-miles) into the eight stage that took the riders into the Swiss mountains on Sunday.
Sanchez, who won a Tour stage last year on his way to winning the best climber's polka-dot jersey, fell on his side before two other riders landed on him.
A tearful Sanchez sat on the ground, clutching his left shoulder and arm, as medical teams tended to him. He could not get back on a bike. He was put on a stretcher and taken to a nearby hospital in Montbeliard in an ambulance.
Tour doctor Florence Pommerie said Sanchez broke his right hand and injured his left shoulder.
"We suspect a dislocated or a broken shoulder," she said. "He also lost consciousness for a couple of seconds, probably because of the pain."
Alejandro Valverde of Spain, one of the two riders who fell on Sanchez, sustained a cut on his shin in the crash, Pommerie said.
Crashes have marred the first week of the Tour and Sanchez became the 20th rider to drop out of the three-week race.
The 157.5-kilometer (98-mile) ride on Sunday from Belfort to the Swiss town of Porrentruy features seven climbs - two of them super-steep.
Sanchez was set to defend his Olympic title later this month.
The Olympic road race is scheduled for July 28. It is not clear if Sanchez will recover from his injuries in time to compete.
Sanchez had started the day in 12th position, 2 minutes and 2 seconds behind Tour leader Bradley Wiggins. He said earlier this week that winning the Olympic road race at the Beijing Games e was the pinnacle of his career, and said he is eager to defend it.