Sir Dave Brailsford is concerned Team Sky has been the victim of computer hacking by critics convinced Tour de France leader Chris Froome is using performance-enhancing drugs.

Froome, during the 2013 Tour which he won, was subjected to sustained interrogations and his performances were pored over by critics, with some using data to justify their stance.

The 30-year-old Team Sky leader has always insisted he competes clean and has described “clowns” interpreting power data as “unhelpful”. He is prepared to be a spokesman for drug-free sport.

Froome led the Tour by 12 seconds on Monday’s first rest day and could extend his advantage in the Pyrenees this week, beginning with Tuesday’s 167-kilometres 10th stage from Tarbes to La Pierre-Saint-Martin ski station.

That would give his detractors, many of whom are active on Twitter, ammunition to fuel their argument which Froome and Brailsford believe is flawed.

Asked if he is ready for the almost inevitable doping questions, Team Sky principal Brailsford said: “It’s part of the game, isn’t it? If he does well (on Tuesday), the rest of the Tour it’s ‘How do you know he’s not doping?’

“The question of how to prove a negative is always going to be a difficult one.

“We think someone has hacked into our training data and got Chris’ files, so we’ve got some legal guys on the case there.

“I would never mention a name (but) ethically and morally if you are going to accuse someone of doping then don’t cheat.”

Team Sky tightly controls access to riders’ data, which can be skewed and does not account for all variables.

Brailsford, who does not have access to all riders’ data, added: “I used to worry about it a lot more, but I don’t any more. It’s part of the game. Just try to be honest, tell the truth, be open.”

Some believe Team Sky is benefiting from financial and technological doping and the British squad was under surveillance by photographers hoping to catch Froome going to sleep on Brailsford’s motorhome by the Parc Beaumont Hotel in Pau on Sunday night.

The former British Cycling performance director, renowned for his meticulous approach, has brought his personal motorhome to the Tour, giving him a base to work and allowing him to sleep in the same environment every night.

Brailsford had hoped Froome would benefit from using a campervan in the same way at the Tour, but the UCI amended its rules after Team Sky had used one for Richie Porte at May's Giro d'Italia.

Subsequently regulations were amended to dictate all riders must stay in the assigned hotels, which range in standard.

Organisers ensure teams are given fair hotel allocation across the three-week race, with teams in five-star accommodation one night and budget hotels the next.

Brailsford argues a good night’s sleep is essential for any athlete and minimum standards of accommodation should be in place.

“This is the nicest hotel we’ll stay in in the whole race. It’s a lovely hotel, it’s great,” Brailsford added.

“The next rest day we’re in Sisteron, we’re in an Ibis, it’s not the best. And it’s next to a slaughterhouse.”

Brailsford’s vision for the future is for Team Sky to not use hotels at all and instead have a mobile ‘performance village’, with everything the team needs, from sleeping vehicles, dining trucks and the mechanics’ vehicles to media, hospitality and fan areas.

“The opportunity to modernise the sport lies in looking at different ways of running the back up side of the sport and the presentation of the sport,” Brailsford added.

“We could do so much more if we had the environment to do it in.”

Brailsford wants a collective vision for the future, but slammed the UCI for its lack of foresight.

He said: “The UCI haven’t got a vision. They haven’t got a document where they can go ‘that’s it’. Ultimately that’s what we should have.”

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