Spain's Joaquim Rodriquez, winner of the third and 12th stages, ignited the race just two kilometres into the 138km stage as he attacked on the climb up the Col du Chaussy in a bid to earn secure further points to boost his lead in the King of the Mountains classification.

He was joined by a group of 25 as they approached the summit of the first climb of the day, but was able to achieve his aim.

Romain Bardet, Rodriquez's main rival for the polka dot jersey,  attempted to respond with an attack on the descent as he had done yesterday on route to his maiden stage victory.

He was unable to repeat his trick Bardet but did the lead in the classification, being the third rider across the 2,067 metres high Col de la Croix de Fer, with only fellow Frenchman Pierre Rolland and Nibali cresting the summit ahead.

The Italian had controversially broken clear of the yellow jersey group while Froome was suffering from a mechanical incident on the climb.

Nibali had opted to attack when tradition normally dictates that rivals of the yellow jersey do not take advantage of such incidents. 

The defending champion, whose chances of overall victory had been significantly diminished during the opening two weeks of the race, was able to surpass Rolland at 16km to the finish on the Col du Mollard before riding solo to the finish in a time of 4 hours 22min 53sec.

Colombia's Nairo Quintana also opted to use the final climb of the day to try to close the deficit to Froome in the overall standings and, having been frustrated on several occasions during the Tour by the Briton, was finally able to break clear and recoup 30 seconds on his rival.

Froome, who claimed he was spat at by a spectator during the stage, still has a 2min 38sec lead over Quintana heading into the final Alpine day of the race tomorrow, where they will finish atop the famous Alpe d'Huez climb.

"I'm looking forward to tomorrow, L'Alpe d'Huez is the most iconic stage and it'll be the last test," Froome said.

"It is a dream to win at l'Alpe d'Huez but I'll race for the yellow jersey.

"All the riders are a bit nervous before that climb because we know the crowd has been partying there for a few nights already.

"But hopefully it won't be any different than in previous years and it won't have any effect on the racing."

The 110.5km stage from Modane Valfréjus to Alpe d'Huez will unofficially crown the winner of the 2015 Tour de France, with the closing stage in Paris considered a ceremonial occasion. 

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