Bloodied Bouhanni takes opening stage in Paris-Nice
France's Nacer Bouhanni celebrates as he crosses the finish line at the end of the first stage of the 72th edition of the Paris-Nice cycling race, on March 9, 2014 in Mantes-la-Jolie, north of Paris - by Eric Feferberg
The 23-year-old, whose left knee was covered in blood as he crossed the line, triumphed in a bunch sprint at Mantes-la-Jolie following a 162.5km stage that was disrupted by several crashes.
German John Degenkolb took second on the stage ahead of Belgium's Gianni Meersman in third.
Due to time bonuses along the course, Bouhanni has a one second lead over Meersman going into Monday's second stage.
It was the second year in a row the 2012 French champion had won a stage in this race, having claimed the second stage last year before crashing out the very next day.
The FDJ rider was reacquainted with the tarmac on Sunday but Bouhanni said he simply put it out of his mind.
"I forgot about the pain in the finish," he said. "My knee was really hurting."
Several times during the race he was seen going back to the doctor's car for attention before positioning himself near the front for the run-in.
It was a poor day for some of the overall favourites as American Tejay van Garderen abandoned at mid-distance with an upset stomach while French hope Romain Bardet and Australia's Simon Gerrans both lost more than a minute after being caught up behind a crash 20km from home.
BMC's Van Garderen, 25, who was fifth in the 2012 Tour de France, pulled out within the first two hours, failing to live up to his pre-race status as one of the favourites.
He had come into the race on the back of a fine runner-up placing behind reigning Tour de France champion Chris Froome in the Tour of Oman.
The race had already been hit by the withdrawal of defending champion Richie Porte, the Australian being switched to the Tirreno-Adriatico race when his Sky team-mate Froome pulled out with a back injury.
Bardet and Gerrans found themselves in the wrong part of the peloton when a crash 20km from home split it into three distinct groups.
And in a race where seconds rather than minutes are expected to decide the winner, losing more than a minute can be terminal to a rider's chances.
Two riders who were well aware of the need for seconds were Team Sky's Geraint Thomas and IAM's Sylvain Chavanel, who both gained a single second on intermediate sprints and will both be hoping to be in contention when the race arrives in Nice.
One rider who is completely out of contention, though, is 2010 Tour de France winner Andy Schleck who finished almost two minutes back in the third group, although the Luxemburger has not been in form since 2011.
Monday's second stage takes the peloton over 205km from Rambouillet to Saint-Georges-sur-Baulche.