Chris Froome (Team Sky) has the experience with three Tour de France titles and the early lead in this 2017 editions, leaving experts scratching their heads on how a rival can beat him.

Cycling Weekly spoke with several managers and directors after the first rest day of the three-week race to understand how, and if, Froome could lose this race.

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“They are one worker down and they look vulnerable, but not Froome,” BMC Racing manager Jim Ochowicz said after returning from an early morning bike ride.

“The workers look a little vulnerable right now. They could run out of gas one day and leave Froome alone, then you have Fuglsang and Aru, both riding on the same team and riding predictably well. That helps.”

Astana and Ag2r look like prime candidates to try and overhaul Sky and Froome (Sunada)

Froome leads by 18 seconds over Fabio Aru (Astana), 51 over Romain Bardet (Ag2r La Mondiale) and 55 over Rigoberto Urán (Cannondale-Drapac). Aru’s team-mate Jakob Fuglsang sits fifth at 1-37 minutes.

“They have to make the race like they did two days ago, hard from the start, like Ag2r did for Bardet. Just a different style and you might be able to wear down the Sky guys.”

BMC Racing’s Richie Porte looked like Froome’s strongest rival until he crashed and abandoned on stage nine.

Now the attention turns to Aru and Bardet with Froome’s top rival from the last years, Nairo Quintana (Movistar) seemingly suffering.

“You have to try to isolate Froome from far out and try to put him a place where he has to respond first-hand to the attacks,” added Trek-Segafredo’s general manager, Luca Guercilena.

“If not, with his team he can manage almost any attack. It’s just that [it’s hard] to isolate him and to attack him.

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“What Ag2r did in stage nine was a smart move, riders ahead in the escape to support Bardet in the final and men behind. Astana, instead, has more possibilities to find a solution like they did in the Dauphiné with Fuglsang and Aru.”

Guercilena’s team races with two-time winner Alberto Contador, but the Spaniard appears far from his best and unable to challenge for the overall.

LottoNL-Jumbo had Robert Gesink for stage wins, but he abandoned along with others like Porte, Geraint Thomas and Rafal Majka after a stage nine crash. The Dutch team still relies on George Bennett in the overall.

“It’s really a shame Richie Porte is out of the race because BMC is a strong block or team that could’ve done something,” general manager Richard Plugge said.

“Aru is strong and with Fuglsang, he has a true helper that’ll make the race interesting. But of course, AG2R is a stronger squad. If you saw how many people they had on Mont du Chat. It’s the biggest block against Sky, but Aru is the biggest rival.”