The Etixx-QuickStep rider’s fracture was confirmed after he crossed the finish line, pushed up the final climb by his team-mates. He will fly to a hospital in Hamburg immediately for surgery.
"Unfortunately, the collarbone is a lateral fracture. The collarbone is in lots of pieces, so it was a major impact. One of the pieces came through the skin, which means it's an open fracture," said Etixx-QuickStep team doctor, Helge Riepenhof.
“Even if it was Tony's wish to start tomorrow, I have to say he is not allowed to," said Riepenhof. "Riders always want to race. Tony especially. He's shown in the last years that even with broken bones that he will race if possible. But this is a medical situation where this is impossible.”
"I can't remember exactly what happened," said Martin, as he tried to describe the crash. "The team put me in a really good position. On the last kilometre no one had the energy left to continue the speed. Everything slowed down, everyone was waiting. Then suddenly I hit the rear wheel of the rider in front of me.
“I thought I almost could stay upright, but then I went into a rider of Giant-Alpecin and I had no balance anymore. I crashed at relatively low speed, with my full weight on the left shoulder."
As the three-time time trial world champion sat on the ground taking the weight off his shoulder area after the crash, it was fairly clear that he had fractured his collarbone. It was a question of how severely, and whether he would be able to start the next stage.
“I felt directly that something was broken. We went to make an x-ray directly after the finish because I was thinking 'OK, maybe I am wrong. Maybe I can start tomorrow'. But now it is confirmed my clavicle is broken," he said.
Because the crash happened with less than one kilometre to go, Martin was given the same time for the stage as the peloton. This means he retained the yellow jersey, despite rolling to the finish several minutes later.
"This has been like a movie, an emotional roller coaster at this Tour," said the 30-year-old. "Now I am really sad. The team gave everything to protect the jersey today. We had again the chance to do it and try to keep it a few more days. It's really been a big success up to this point."
While it was a bad day for Martin, there was some good news for the Etixx-QuickStep team with three-time cyclocross world champion, Zdeněk Štybar winning the 191.5km stage.
"With Štybar it was such a good moment. It's so strange to be so sad and happy together," said Martin. "I told Štybar to not be sad for me. I told him to enjoy his day, as he deserves it. I am sure the team will keep the morale high. That's the Tour de France."
Martin will travel to Hamburg, Germany for surgery immediately owing to the severity of the fracture. "I really wish I could continue, to even just start tomorrow, even if it is broken," said Martin. "I wish I could honour the jersey and show it one last time with a ceremony at the start. I could enjoy it a little more than I have the last days and then stop.
"But it is now clear I need to go to the hospital for surgery immediately, and my race is over. It's hard to accept. I'd like to keep fighting. But the doctor has the last word, and when he says there is no way to continue I must accept this."
Martin's departure from the Tour means the yellow jersey will return to Chris Froome (Sky), who was also caught up in the crash. The winner of the 2013 Tour de France was sitting 12 seconds behind Martin on the general classification at the end of Stage 6.
Froome briefly took the overall lead ahead of Stage 4 after yellow jersey wearer, Fabian Cancellara (Trek Factory Racing) was forced to abandon the race with two broken vertebrae.