Sir Dave Brailsford has predicted the Tour de France will be a "battle royale" between Chris Froome, Alberto Contador, Vincenzo Nibali and Nairo Quintana.

The quartet are widely regarded as the best stage racers of the current generation and will go head to head over a challenging route containing six mountain-top finishes, several classics-style stages and two time trials.

All four are Grand Tour winners, with Froome, Contador and Nibali all past Tour champions, and Brailsford anticipates a thrilling spectacle from July 4-26.

He told Sky Sports News HQ: “What we do have is a great competition on the horizon. We have got four of the world’s best riders all going head to head. It’s the first time they are all going to be in top form at the Tour de France and it is hard to choose between them. 

“Alberto Contador, one of the greatest general classification riders of the modern era, and Nairo Quintana is a brilliant climber, so he’ll come into his own in the second half of the race where it becomes very mountainous. They have all got different skill sets so it’s setting up for a battle royale.

“The race is basically two halves this year – there is the first half through Northern France and it starts in Holland and Belgium, which is more like a series of one day races, and that’s where Nibali will be at his best.

“Chris is probably the most complete. He time trials really well, he climbs fantastically well."

Brailsford named Froome as leader of a Team Sky squad also including Richie Porte, Geraint Thomas, Peter Kennaugh, Ian Stannard, Luke Rowe, Nicolas Roche, Leopold Konig and Wout Poels on Monday.

He added: “We study the route very carefully and split it down to its component parts. We always analyse the demands of the event and figure out what it is going to take to win.

“We have a performance strategy and then we decide on the kind of riders, the style of riders that we want, then we select riders to fit those roles. They've all got their different roles to play and if they all perform to the best of their ability I'm sure we will win the race."

Froome won the Criterium du Dauphine earlier in June in his last race before the Tour and Brailsford was encouraged by the 30-year-old's performance.

“He’s in good shape,” he added. “He’s healthy, fit, and hungry and everything has fallen into place nicely for his assault on the Tour this year so it is exciting and we are ready to go."

Brailsford also addressed issues regarding drug testing after Froome admitted to missing a test while on holiday this year due to overzealous hotel staff.

Froome said that staff would not allow testers up to his room or inform him that they were even there, and Brailsford said there was no issue over the incident.

He said: “Team Sky wants to take a leadership position in trying to demonstrate that this is a clean sport and it can be done clean. That’s our situation and it always will be.

“With regards to Chris, he missed his first test in 2010 and one more recently but I was satisfied - he phoned me straight away. He was at a hotel, the receptionist wouldn't allow the tester to go to his room, (they said) ‘you can’t disturb our customers’, they wouldn't phone up. He didn't know they were there.

“He came down for breakfast and was told by the hotel staff that they had been there to try and test him and I don’t think there is any cause for concern there. We actually helped him with an appeal.”

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