Chris Froome guillotines his big Tour de France rivals on Bastille Day

A few hundred metres before the finish here the road swings across the rocky mountainside in a vast, shallow hairpin bend which takes just under a minute to cover at Tour de France speed. As Chris Froome rode through the bend in his yellow jersey towards the little summit which marked the finish line there was no sign of the second man on the road, Nairo Quintana, nor even of one of the motorbikes which precede key riders close to the finish.

It was as good an image as any of the devastating impression the Kenyan-born Briton made on the first mountaintop finish of this Tour, but there was more. When Quintana did hove into view, just about a minute after Froome had headed towards the finish line, the Colombian was accompanied by none other than Richie Porte, Froome's team-mate at Team Sky, who left Quintana standing to take second place on the stage and deprive him of a handful of time bonus seconds.

The first mountaintop finish in any major stage race is always a key moment as the contenders discover precisely where they stand. The bluffing ended here with a brutal reckoning on a climb which is, in essence, the lengthy, steep drag up the north side of the Col du Somport, with early passages that looked as steep as the side of a house and a steadier drag into the finish. The 2014 winner, Vincenzo Nibali, will now struggle to finish on the podium having been dislodged a massive nine kilometres from the finish and losing well over four minutes.

“I am not even the little brother of last year’s Nibali,” said the Italian, who complained of being unable to breathe or follow his team-mates.

Alberto Contador’s thoughts of a Tour-Giro double died here; he still has a chance of making the first three but is now four minutes back in the standings and sixth overall.

“I couldn’t breathe, I couldn’t turn my legs,” he said. He lies one place behind Geraint Thomas, which should worry him, because if the Welshman continues to climb with this brio he will act as a perfect second foil for Froome, able to mark any threatening attacks.

Froome was poised for attacks from Nibali, Contador and Quintana but they never came; instead came the news that Nibali and Contador had lost ground. That was the prompt for the hammer to go down; the final attack came while the gradient was still steep enough to make a difference, with enough level road to the finish for the time gaps to be stretched out painfully before he took what looked close to a carbon copy of his Bastille Day win on Mont Ventoux in 2013.

Of Froome’s “Fab Four” fellows, only Quintana came near living up to his billing, surviving when Porte put in the initial surge just over seven kilometres out to dispose of Contador and most of a select 11-rider group that had got through the toughest section of the climb alongside the yellow jersey. But a second searing attack, this time from Froome a kilometre later led the Colombian to cede ground, as the 2013 Tour winner sprinted to open the initial gap.

Both Quintana and the “fifth Beatle”, Tejay van Garderen, opted for damage limitation, and while the American finished 2:30 back, his first-class opening week means he lies second overall, but nigh on three minutes back, just ahead of the Colombian.

There were surprises: Thomas was the first, the biggest was the 22-year-old Briton Adam Yates climbing seamlessly into seventh on the stage, but another was the accident-prone Dutch climber Robert Gesink. His Lotto-Jumbo team have had a quiet season and he has not performed at this level – for a variety of reasons, some physical, some domestic – since finishing sixth in the 2012 Vuelta, but is now eighth overall.

This was, lest we forget, Bastille Day, when French spirits stir and their cyclists come under immense pressure to win the Tour stage on the day of La Fête Nationale. They have been frustrated since David Moncoutie won in 2005 and the pattern continued as their brightest overall prospects, Romain Bardet, Thibaut Pinot and Jean-Christophe Peraud, slipped inexorably behind well before the final attacks began.

The home nation retains Tony Gallopin in seventh overall while Warren Barguil crashed but fought through to lie 10th in the standings.

But it is light years from the hopes that were raised when Peraud and Pinot finished on the podium last year.

Underneath the mountaintop where this finish is situated lies one of the world’s greatest cave systems, Le Gouffre de Saint Martin – the Gulf of Saint Martin – up to 2.1 km deep, and covering 140 sq km. With characteristic understatement, Froome said he would not like to be in his rivals’ shoes on Tuesday night; the best-laid plans of Quintana, Contador and Nibali might as well have been torn up and thrown down the vast cavern as the gulf between Sky and their adversaries was there for all to see, with two more days climbing through this mountain range to come.

Ireland’s Dan Martin came home in 57th position, 11:34 behind Froome and is now 21:05 down on the yellow jersey.

Nicolas Roche was 75th, 13:51 behind, and is now 39:26 off the pace, while Sam Bennett finished 23:21 behind.

(Guardian service)