AUTUN, France (AFP) - The Tour de France campaign of yellow jersey contender Andreas Kloden could be over, if fears over a fractured coccyx are confirmed by a scan, said his team manager here Thursday.

Kloden was among the numerous riders who crashed in a dramatic fifth stage, the race runner-up landing in a grassy ditch by the side of the road at the 107km mark.

His team leader, Alexandre Vinokourov also crashed, the Kazakh hitting the tarmac while racing at over 60km/h as the bunch continued their pursuit of a four-man breakaway over some tight, winding roads.

It meant Vinokourov, a third place finisher in 2003, finished the stage over a minute in arrears.

However Astana team manager Marc Biver is more concerned about Kloden.

"I'm worried about Kloden. He seems to have a fracture of the coccyx," Biver said after the stage.

Both Kloden and Vinokourov were taken to hospital to be checked over.

If Kloden's fracture is confirmed his campaign is likely to be over. The German, a former team-mate of 1997 winner Jan Ullrich, finished runner-up to Lance Armstrong in 2004 and came third last year.

Biver added: "To look at, Vino's injuries appear a lot more serious than Kloden's. But Andreas is feeling pain on his back, and his hip.

"But we'll see. We have to consult the team doctors, and we'll have a review of things tomorrow morning. Hopefully their injuries won't stop them from getting a good night's sleep which will help them recuperate."

"The Tour is three weeks long, and there's a lot of things that can happen. The proof of that is that our two team leaders crashed today. Friday the 13th is tomorrow, so we'll see if the day goes differently for us."

He added: "If these kind of accidents prevent us from contending for overall victory, then we'll put it down to fate. There's not much we can do about that.

"It would be a pity to lose the Tour like that, but life goes on."