Peter Sagan won stage two of the Tour de France to take the race leader's yellow jersey from Mark Cavendish.
The world champion took a tight victory in Normandy after the peloton caught breakaway rider Jasper Stuyven in the final 500 metres of an uphill finish.
Cavendish finished one minute 45 seconds behind Sagan in what was always going to be a tough stage for him.
Defending champion Chris Froome and rival Nairo Quintana finished together, but Alberto Contador lost 48 seconds.
Two-time winner Contador, who has geared his entire season around trying to win this year's Tour, crashed for a second time in two days as early rain made for treacherous conditions on the roads from Saint-Lo to Cherbourg-en-Cotentin.
He bruised the right side of his body in a heavy crash during Saturday's opening stage and hurt the other side on Sunday and looked in discomfort as he crossed the finish line.
"I lost more time than I had hoped to," said the 2007 and 2009 winner.
"The Tour has really started on the wrong footing. I'm not happy at all. I must see if I can make up some time in the Pyrenees and the Alps.
"I'm physically hampered. I cannot pedal as I would like as a result of the crashes. The important thing is to keep my morale, not fall apart, which is sometimes complicated."
Who else lost time?
Australia's Richie Porte, a former Team Sky rider who is now BMC's general classification hope, finished one minute 45 seconds behind Froome after suffering a puncture late on.
"It was a disaster, but what can you do?" he said. "I was sitting second wheel in perfect position. I don't know what the hell I hit, but the next thing I know I had a flat. The Tour is far from over, but it's quite a hard one to take."
Geraint Thomas, Team Sky's 'plan B' should Froome drop out of contention, also lost out. He too suffered a puncture, about 30km from the finish, and although he managed to get back into the peloton, he could not go with the attacks on the final ascent, and is now 38 seconds adrift.
Slovak Sagan, a Tinkoff team-mate of Contador, will wear the yellow jersey for the first time after winning his fifth Tour de France stage.
He went into the stage as favourite to win with the uphill finish ideally suiting him and the 26-year-old lived up to his billing with a well-timed sprint to the line.
Sagan was passed by French hope Julian Alaphilippe in the closing 200m but he kicked again to beat the Etixx-Quick-Step rider by a bike length, with Spain's Alejandro Valverde third.
However, he admitted he did not realise he had even won the stage, which finished at the top of a two kilometre ascent.
Sagan said: "I'm very surprised I won because I was thinking there were still two guys out front and then I finished and I found out I won. I'm very happy.
On winning his first yellow jersey, he added: "It's unbelievable. I'm already wearing a nice jersey (referring to his world champion rainbow bands) so yellow is very nice for me."
How the race unfolded
A group of four riders broke clear early on in the stage, building up an advantage of more than six minutes, before the peloton, which was led by Cavendish's Dimension Data team-mates, began working together to bring them back.
Italian Cesare Benedetti was the first to drop out of the quartet and when his Bora-Argon 18 team-mate Paul Voss and Vegard Breen of the Fortuneo-Vital Concept team started to slow on an ascent with 8km remaining, Stuyven attacked.
However, the Belgian Trek-Segafredo rider's two-minute advantage disappeared with the finish line in sight as Sagan sprinted by.
What happened to Cavendish?
The Manxman was well looked after by his Dimension Data team-mates, riding near the front of the peloton for most of the stage.
However, the hilly finish was never going to suit a pure sprinter and although he said he "respected the jersey" by riding hard to the finish, he lost more than a minute on the ascent.
He also lost the lead in the race for the green points jersey to Sagan, however, because the Slovak will ride in yellow on Monday's third stage, Cavendish will wear green.
Monday's 223.5km race from Granville to Angers is expected to end in a bunch sprint where a Cavendish win would see him equal Bernard Hinault's tally of 28 stage victories to move second, behind Belgian legend Eddy Merckx, who has 34, on the all-time list.
You can follow Cavendish's progress from 12:00 BST in BBC Sport's live text commentary, with BBC Radio 5 live commentary on the website from 15:00 BST.
Stage two result:
1. Peter Sagan (Svk/Tinkoff) 4hrs 20mins 51secs
2. Julian Alaphilippe (Fra/Etixx - Quick-Step) Same time
3. Alejandro Valverde (Spa/Movistar)
4. Daniel Martin (Ire/Etixx - Quick-Step)
5. Michael Matthews (Aus/Orica BikeExchange)
6. Wilco Kelderman (Ned/LottoNL)
7. Tony Gallopin (Fra/Lotto)
8. Greg Van Avermaet (Bel/BMC Racing)
9. Bauke Mollema (Ned/Trek)
10. Chris Froome (GB/Team Sky)
General classification after stage two:
1. Peter Sagan (Svk/Tinkoff) 8hrs 34mins 42secs
2. Julian Alaphilippe (Fra/Etixx - Quick-Step) +8secs
3. Alejandro Valverde (Spa/Movistar) +10secs
4. Warren Barguil (Fra/Giant) +14secs
5. Chris Froome (GB/Team Sky) Same time
6. Greg Van Avermaet (Bel/BMC Racing)
7. Nairo Quintana (Col/Movistar)
8. Roman Kreuziger (Cze/Tinkoff)
9. Simon Gerrans (Aus/Orica BikeExchange)
10. Daniel Martin (Ire/Etixx - Quick-Step)