CONTRES, France Tour de France champion Alberto Contador lost time on the leaders and suffered a painful knock to his leg when he crashed towards the end of the first stage of Paris-Nice on Monday.
The race favourite crashed three km from the finish in Contres after being dropped from the front following a harsh effort by the Caisse d'Epargne team of last year's winner Luis Leon Sanchez.
New Zealand's Greg Henderson won the 201.5-km stage beating Slovenia's Grega Bole and France's Jeremy Galland on the line.
"I picked up a pretty good knock. The pain is quite sharp. I am quite worried," Spaniard Contador told reporters.
"I was on the left side on the road and there was a wave in the peloton. I fell in the grass with Heinrich Haussler.
"It was quite a hard fall but as I was still over three km from the finish I had little choice but to come back into the bunch."
The Astana rider's team manager Yvon Sanquer said Contador was bruised but would start Tuesday's 201-km second stage to Limoges.
Prologue winner Lars Boom retained his overall lead, but Contador, who won Paris-Nice in 2007, is 25 seconds behind in the standings, in eighth place.
"It's not the time lost I'm worried about but how I will feel in the morning," Contador said.
Germany's Jens Voigt stayed second overall, five seconds behind Dutchman Boom, and Briton David Millar moved into third, 13 seconds adrift.
Henderson, a former track rider who won his first major road laurels last year on the Tour of Spain, outsprinted the leading group of 17 riders for victory.
"I won a sprint in slow motion because we were all so tired because of the cold and wind," said Henderson, who gave his Team Sky their first pro victory in Australia in January.
American Levi Leipheimer was another of the big names to lose time in the treacherous stage. Held back by one of several pile-ups in the peloton, the RadioShack team leader lies seventh overall, 25 seconds behind Boom.
(Editing by Alison Wildey and Sonia Oxley;
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