Team Sky brought its A game to the to the Tour de France this July and others have not, says team boss Sir Dave Brailsford ahead of Thursday’s stage 18 mountain time trial to Megève.

Sky’s Chris Froome strengthened his overall lead on Wednesday afternoon riding away from his rivals on the heels of an attack by Richie Porte (BMC Racing). Froome leads the overall classification by 2-27 minutes over Dutchman Bauke Mollema (Trek-Segafredo), who faded in the final two kilometres of the Finhaut-Emosson summit finish.

“I’m not sure that we are riding above our best, maybe the others aren’t at their best, would be my interpretation,” Brailsford said standing in front of Sky’s bus and near his rivals’ mobile headquarters parked on the Emosson Dam.

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“It’s not easy. The same for the Olympics in Rio in a couple weeks time. The British cycling team have always managed to up their game and deliver their A game when it really matters,” continued Brailsford.

Team Sky on stage 15 of the 2016 Tour de France (Watson)

“That’s an important part in managing a team and the riders, and helping them deliver that. You want your PBs when it matters the most, and that’s not easy.”

If Sky delivers as it hopes, Froome will defend his lead in the next three Alpine stages and ride on to the Champs-Élysées in Paris on Sunday as victor for a third time.

Spanish team Movistar had been expected to challenge Froome in this 2016 edition with young 26-year-old Colombian climber, Nairo Quintana. The same for Alberto Contador (Tinkoff), who abandoned after crashing twice. And Froome’s former team-mate Richie Porte and his American WorldTour team BMC Racing.

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“I’ve been to a lot of tournaments over the years. The challenge in a big event like the Olympic Games, the World Championships or the Tour de France, is that you have to turn up with your A game, and it’s not easy to turn up with your A game when it really matters,” Brailsford added.

Movistar rival Nairo Quintana has failed to gain any time on Chris Froome in the mountains so far

“Sometimes it really works and you do it, and some times you don’t quite get it right. That’s the strength of the Movistar team. They are a fantastic team, they’re above us in the WorldTour, they’ve won more races than we have, they are a brilliant team, but for the moment, we’ve turned up our A game.”

Brailsford underlined that he was analysing his team’s performance and that at other times in the season his rivals ruled.

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“A few weeks ago in the Giro d’Italia, we weren’t talking in the same way, and we have a Vuelta a España coming up and I’m sure that’ll be a different story again,” he said. “In that since, you have to decide your priorities and how you can turn up with your best team. 100 per cent of everyone, and if they are only 70 per cent strength then 100 per cent of that 70 per cent.”

The Tour matters first to the British team, who started in 2010 with the aim of having a winning Tour de France within five years.

“We said we wanted to win a monument. We really wanted to give the Giro a good go with Mikel Landa, and that didn’t work out, and we wanted to win the Tour de France. If you can win one race and no other in a season, then it’d be this one.”