Matteo Trentin of Italy won the seventh stage of the Tour de France in a photo finish, after a group crash and a hilly final section split the pack.
Fellow Italian Vincenzo Nibali retained the overall lead.
US rider Tejay van Van Garderen, who crashed within the last 17km, was the big loser on the day as his fall costing him more than a minute in the title chase.
The sun finally broke through clouds that had dumped rain over riders in recent days for the 234.5km ride from Epernay, the capital of Champagne country, to the eastern city of Nancy.
Trentin, a 24-year-old rider who won a stage in the Tour of Switzerland earlier this year, beat Slovakia's Peter Sagan by what looked like no more than a centimeter or two on the finish-line photo of the final sprint.
Trentin patted the Cannondale rider on the back after crossing the line. Sagan, who has come close several times, has yet to win a stage this year. France's Tony Gallopin was third.
BMC leader van Garderen was not the only American to have a bad day. Andrew Talansky fell in the final sprint, rolling over and scuffing up his left arm after getting hit by Australia's Simon Gerrans.
But under course rules, Talansky, the Garmin-Sharp team leader, did not lose time in the title chase because his crash happened within the last 3km.
Overall, Nibali has a two-second lead over Astana teammate Jakob Fuglsang and is two minutes, 37 seconds clear of Alberto Contador, his main rival. Talansky is seventh two minutes, five seconds back.
"There have really been a lot of crashes this year, in the final sprints," Nibali said. "We all knew that Sagan wanted a win today ... The end of the stage was very hard."
Overall van Garderen trails 3 minutes, 14 behind Nibali, in 18th place, after starting the stage only 2:11 minutes adrift.
A shakeout among the title contenders could be ahead in Saturday's eighth stage, which winds through medium-height mountains along a 161km course from Tomblaine to Gerardmer La Mauselaine.