Richie Porte tumbles from Tour de France top 10

Sky went from plan A, plan B to plan unknown today in the Tour de France after Richie Porte lost 8-48 minutes to the overall leader Vincenzo Nibali. The Australian, who sat second overall this morning, slipped to 16th at the top of the Chamrousse climb.

"I don't think I dealt with the heat very well," said Porte. "It's one of those things. It's a massive shame but we'll see what happens tomorrow.

"I feel more for my team-mates who have been brilliant for me every day. If it happens to me then it can happen to other guys too. We'll just keep on pushing."

Porte lost ground on the leaders early in the 18.2-kilometre Alpine climb at 12.4 kilometres. Geraint Thomas, who lost ground earlier, and Mikel Nieve paced him to the line, but it was clear that this was not the same Porte from earlier in the Tour.

"There wasn't a lack of hydration, but that's something to consider," Sky's team boss, David Brailsford explained. “I don't know what happened, that's the honest answer, but obviously it wasn't the Richie that we've seen for the first part of the race.

"No doubt at the bottom of the climb today he felt the heat, but I don't think that we can give any excuses today, it was the same for everybody. You have your good days and bad days, and when the bad days come you just have to keep going on."

Sky went on after Chris Froome – plan A – crashed and abandoned in the fifth stage to Arenberg. Porte, who helped Froome win in 2013 and Wiggins in 2012, became the leader.

With the Australian now sitting 11-11 minutes behind Nibali, Brailsford will have to have a talk with the staff and riders tonight about the team's plan C.

"We are not going to roll over,” Brailsford continued.

“It was a blow losing Chris. We re-calibrated to our plan B and now we have to re-calibrate again, you just have to take stock and not get too downbeat.

"I don't know [if the podium is out of reach]. We have to see about the next two days and we can look to animate the race as much as possible."

Brailsford said that the team could consider going for stages instead of the overall. He added, "I don't think we just go around and follow."

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