Great French hope Romain Bardet faces a Tour de France moment of truth in the Alps Thursday in his bid to become the first home winner since 1985.

The 27-year-old has given French cycling fans hope by battling shoulder to shoulder with reigning champion Chris Froome over the last two and a half weeks.

The yellow jersey contenders are all agreed that the Tour will be decided on Thursday's final climb -- a whopping 14.1km long ascent with an average gradient of 7.3%.

So it is now or never for Bardet as he sets off on the 179.5km Alpine 18th stage from Briancon to the Col d'Izoard in third place, just 27 seconds back from Froome.

Following Wednesday's 17th stage where Bardet put in several attacks on the final climb, the Galibier, he vowed: "I'll try again tomorrow!"

"This stage is the equivalent of (last year's) Mont Ventoux on this year's Tour de France," said Froome, 32.

"It's the most iconic mountaintop finish -- let's see what happens."

The reigning champion leads by just 27 seconds from Rigoberto Uran and Bardet, with Fabio Aru 53sec back.

"It's definitely the closest Tour I've ever been in to this point. I knew it would be," added the Sky team leader and three-time champion.

"It's still a very open race keeping in mind (the) big summit finish on the col d'Izoard."

- Confident -

As well as holding the yellow jersey, Froome also knows he's the best time-trialer in the top 10 and with a 22.5km race against the clock to come in Marseille on Saturday, he's feeling confident.

"It's not a massive margin when you compare it with other years at this point, but it's a margin I'm nonetheless happy with.

"Certainly if I went into the time-trial on Saturday with this margin, I would feel pretty confident."

He also believes his rivals need to attack him.

"I imagine they will try and I have to be ready for that."

Bardet was eager to attack all day on Wednesday and his team even had to tell him to wait on the Galibier as he wanted to attack 8km from the summit.

When he did start putting in a few bursts of acceleration, he managed to dislodge Aru, who went on to lose 31sec.

"You have to be patient and consistent at the Tour de France. The race isn't over," added Bardet.

It certainly isn't and not for the king of the mountains polkadot jersey either.

With a first category climb and then double points on offer at the Izoard summit, the jersey could still change hands before Paris.

Slovenian Primoz Roglic took 42 points during Wednesday's 17th stage, which he won, and now sits 49 points behind Warren Barguil.

But he will have to crest the Col de Vars first and then win the stage to have any chance of claiming the polkadot jersey.

"I think it will be difficult," warned Barguil.

Source: AFP