Tour de France: Injuries, crashes and inexperience push Chris Froome and Sky to the limit

Long and winding road: The peloton climb a hill during yesterday’s Stage 14 of the Tour de France, which finished in Lyon and was won by Matteo Trentin (Getty Images)

It all looks so familiar: just like in 2012, a Team Sky leader has taken the yellow jersey on the first summit finish of the Tour and then swept his rivals from the board with a dramatic time-trial performance. From hereon, we thought, pressing the replay button in our memories, all Sky have to do is keep the race under control as they did so brilliantly last year for two long weeks to Paris and it's game over.

But somewhere the film has jammed and the images of 2012 have started to blur. Chris Froome, as had been predicted since he began winning races at the same velocity as Sir Bradley Wiggins, remains in yellow, but his team are in difficulties. And their predicament seems to be worsening. The alarm bells began ringing last Sunday in the Pyrenees, when Sky lost Belarus powerhouse Vasil Kiryienka, then Richie Porte dropped from second and lost 18 minutes, and Froome was isolated for 110 kilometres in a group with 60 rivals. That he did not lose time that day says a lot about his individual strength – but also about the strategic errors of Spaniards Movistar, the most powerful team that day. Movistar were overly concerned with eliminating Porte from the running rather than knocking Froome off his perch – and the Briton could breathe again.

Then on Friday, Sky took an even bigger blow, as Froome himself lost 69 seconds to arch-rival Alberto Contador on a day when crosswinds and ultra-aggressive riding by rival squads Belkin, Omega Pharma and – above all – Saxo-Tinkoff, left Sky on the back foot again, with their weaknesses exposed.

"The lads got caught out," was the succinct analysis of Sky general manager, Sir Dave Brailsford. But the team's woes go deeper.

Froome came close to admitting yesterday how costly to him the absence of Wiggins has been on this Tour, despite the strained relationship between the pair. "Having Brad would definitely have upped our ranks both in the mountains and on the flats," the 28-year-old said. "He's quite a versatile rider in that respect."

Also missing from the line-up are both Edvald Boasson Hagen, who crashed out injured on Wednesday and Kiryienka, who rode himself into the ground supporting Froome and Porte in Sky's difficult day in the Pyrenees.

Both were hefty, ultra-reliable, experienced team workers, more than capable of defending Froome and keeping him in contention when Friday's cross-winds shattered the peloton. Others like Britons Pete Kennaugh, Geraint Thomas and Ian Stannard are equally at home in such difficult conditions. But all three are carrying injuries or have had bad crashes early on: Kennaugh after falling down a mountain-side in the Pyrenees, Thomas with a cracked pelvis since the first stage, Stannard some knocks from the same crash that poleaxed Thomas.

The three remaining riders, Porte, Kanstantsin Siutsou and David Lopez have all had uneven form. Second on the first Pyrenean stage, but 18 minutes down in the second, Porte seemed to be bouncing back in the time trial, where he finished fourth. But on Friday, he lost another 10 minutes, which he summed up succinctly as being a "shit day".

Questions are beginning to be raised whether Sky have brought the right line-up of support riders, packed with climbers for the mountains but lacking all-rounders. Two who would have surely shone in Friday's brutal weather conditions were Austrian Bernhard Eisel, Mark Cavendish's old wingman, and – as Froome has mentioned – Wiggins, who is slowly recovering from injuries.

The experienced hand of Sean Yates – Sky's sports director who quit for health reasons last year and who would have thrived as a rider in Friday's difficult conditions – could also be missing. As for Mick Rogers – a rock of support for Wiggins in 2012 – he has been signed by Saxo-Tinkoff, and masterminded Friday's mass attack.

With Sky lacking in experienced riders, depleted and battered, Froome himself has been taking risks – for example, using one rider, Stannard as his lone wingman in the finales, rather than the usual three or four. Riders like Porte, Kennaugh and Thomas are dropping back in the later parts of the stages. They are "energy saving" strategies to ensure strength is at a maximum come the final week through the Alps. But as happened on Friday, they limit Froome's room for manoeuvre – and Sky are forced to gamble higher than they would like.

The odds that today Froome will regain the upper hand with an all out assault on Mont Ventoux. And on set-piece mountain stages, which Sky excel in, they will almost certainly once more lay down the law. But in the four days of Alpine racing that remain, his squad will be needed to help him defend that lead. As one of France's most respected cycling commentators, former professional Jeff Bernard, put it yesterday: "You can't win a Tour riding alone."