Defending champion Chris Froome extended his overall lead in the Tour de France as Peter Sagan won stage 11.
Sagan won a sprint after he, Tinkoff team-mate Maciej Bodnar and Team Sky's Froome and Geraint Thomas launched a surprise attack late in the 162.5km stage from Carcassonne to Montpellier.
Froome, who finished six seconds clear of the peloton, collected a six-second bonus for his second-place finish.
He now leads fellow Briton Adam Yates by 28 seconds and Nairo Quintana by 35.
Mark Cavendish, who had been among the favourites to pick up a fourth stage win of this year's race and 30th overall, finished well adrift after suffering a mechanical problem late on.
Thursday's planned finish on top of Mont Ventoux has been cancelled because of high winds in Provence. The 12th stage will now finish several kilometres down the mountain at Chalet Reynard.
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- 'That was bonkers' - how Froome extended lead
An unlikely alliance on a 'crazy' stage
With cross winds threatening to split the race throughout the day, riders were watchful and an early break by Arthur Vichot and Leigh Howard was brought back with 60km remaining.
The peloton then rode more conservatively until Sagan broke clear inside the final 15km with Pole Bodnar.
Froome, spotting an opportunity to gain time on his rivals for the general classification, followed with compatriot Thomas and the unlikely quartet quickly opened a lead of more than 20 seconds which the disorganised peloton only managed to reduce to six by the finish.
"It was crazy," said Sagan. "Froome and Geraint came with us and I said, 'we are too strong, they are never going to catch us'. So we pulled hard and it happened.
"There was a crazy wind and I was not planning to go in the break with the yellow jersey and Geraint and Bodnar. You cannot plan that - it just happens."
Sagan picked up 67 points in the green jersey classification - 50 for winning the stage and 17 in an intermediate sprint - and the Slovak now leads Cavendish by 90 points and looks certain to win a fifth successive title.
Feisty Froome extends lead
Two-time Tour winner Froome moved into the race leader's yellow jersey with a surprise downhill attack on stage eight into Bagneres-de-Luchon and he followed that with another aggressive move on Wednesday.
It is unusual to see the race leader attack on a flat stage but with the sprinters' teams assembling themselves for the run-in to Montpellier, he made a bold decision.
"Obviously I took a few seconds on the downhill and then again on the finish here," the 31-year-old said.
"Any opportunity I can see I'm going to take it.
"This is bike racing at its best. I feel like I'm enjoying it, I'm not feeling I'm being forced into this because of pressure."
Stage 11 result:
1. Peter Sagan (Svk/Tinkoff) 3hrs 26mins 23secs
2. Chris Froome (GB/Team Sky) Same time
3. Maciej Bodnar (Pol/Tinkoff)
4. Alexander Kristoff (Nor/Katusha) +6secs
5. Christophe Laporte (Fra/Cofidis) Same time
6. Jasper Stuyven (Bel/Trek)
7. Edvald Boasson Hagen (Nor/Dimension Data)
8. Andre Greipel (Ger/Lotto)
9. Sondre Enger (Nor/IAM Cycling)
10. Oliver Naesen (Bel/IAM Cycling)
General classification after stage 11:
1. Chris Froome (GB/Team Sky) 52hrs 34mins 37secs
2. Adam Yates (GB/Orica) +28secs
3. Daniel Martin (Ire/Etixx - Quick-Step) +31secs
4. Nairo Quintana (Col/Movistar) +35secs
5. Bauke Mollema (Ned/Trek) +56secs
6. Romain Bardet (Fra/AG2R) Same time
7. Sergio Henao (Col/Team Sky)
8. Alejandro Valverde (Spa/Movistar) +1min 13secs
9. Tejay van Garderen (US/BMC Racing) Same time
10. Roman Kreuziger (Cze/Tinkoff) +1min 28secs