Chris Froome is hoping to keep hold of the 2015 Tour de France race lead after Sunday's team time trial, but expects a strong challenge from Tejay van Garderen's BMC squad

Tour de France leader Chris Froome has said that Team Sky are ready for today’s key team time trial stage in Brittany, but predicts a hard fight to retain the yellow jersey – not least from overall rival Tejay van Garderen and his BMC squad.

The undulating TTT route from Vannes to Plumelec finishes with a 1.7-kilometre climb, Côte de Cadoudal, which will drain riders of any energy they have left after nine straight days of racing. The TTT stage usually appears earlier in the race, so fatigue and injury will play a part in deciding the outcome of this key stage.

Froome said that several Sky riders kept something back during Saturday’s stage, mindful of the effort required today: “We really did try and approach the stage quite conservatively as a team given in the back of our minds we have the team time trial tomorrow,” said Froome after Saturday’s stage to Mûr-de-Bretagne.

Chris Froome on stage eight of the 2015 Tour de France

Chris Froome on stage eight of the 2015 Tour de France, where he finished in eighth place

“That’s really quite an important stage for us. That’s a day where half a minute could be won or lost depending on how it goes.

“It’s going to be tough, especially with BMC breathing right down my neck and Tejay right there. But we’ve got a really strong group of guys for the team time trial and hopefully we can be up there with the best.”

BMC are the current team time trial world champions, and won the Critérium du Dauphiné TTT in June, where they beat Sky by a significant 35-second margin to unseat Sky’s Peter Kennaugh from the race lead.

BMC’s line-up includes stage one winner Rohan Dennis, who was also the rider that took the lead from Kennaugh in the Dauphiné. This time, they are riding for van Garderen who goes into the TTT just 13 seconds behind Froome in the general classification.

Tour de France profile stage 9

The team time trial stage nine is far from flat: pacing will be key to setting a good time

“With the team I have and what they have shown so far, I think we are pretty confident,” van Garderen said. “We are just going to go out there and ride as hard as we can. We have four world champions in that discipline on the team, so we will put out the best performance that we think we can.”

Both BMC and Sky have so far not suffered the loss of riders through injury that has affected other teams, notably top TTT performers Orica-GreenEdge. The Australian squad won the Tour de France TTT in 2013, setting a new record for the fastest average speed of any Tour stage in history – an astonishing 57.841kmh.

This year, however, Orica has lost Simon Gerrans, Daryl Impey and Michael Albasini to injury in the opening week and are down to six men. One of those – Michael Matthews – is suffering from broken ribs, despite continuing in the race. Each team must finish with five riders, leaving Orica with little margin for riders dropping out or falling back.

Etixx-QuickStep and Trek Factory Racing are also without their time trial powerhouses Tony Martin and Fabian Cancellara, both of whom withdrew from the race due to crashes while in the race lead.

The Tinkoff-Saxo, Movistar and Astana teams of GC contenders Alberto Contador, Nairo Quintana and Vincenzo Nibali have fared better. Movistar in particular have a contingent of strong time trial riders, including British national champion Alex Dowsett and Italian TT specialist Adriano Malori that could provide an upset.

After the TTT, the riders travel south for the race’s first rest day on Monday before tackling the Pyrenees.

Video: Tejay van Garderen’s BMC Time Machine