CHRIS Froome expects to be on his best form in the final week of the Tour de France as he fights to hold on to the yellow jersey in the closest battle this race has ever seen.

Just 29 seconds cover the top four as Team Sky’s Froome leads by 18 seconds from Italian national champion Fabio Aru, with Frenchman Romain Bardet a further five seconds back in third and former Sky rider Rigoberto Uran of Colombia looking ominous in fourth.

The race will head towards the Alps after yesterday’s rest day, with stages tomorrow and Thursday potentially decisive before Saturday’s time trial in Marseille.

Three-time Tour winner Froome is used to beginning the final week of the race with a decent cushion to defend, but struggles in the Pyrenees saw him temporarily surrender yellow and left his rivals bunched up behind him.

However, after taking a different approach to his preparation this year, Froome believes he is just about to peak.

“I certainly feel as if I’m on an upward curve,” the Briton said. “I came in with the least amount of race days ever coming into a Tour de France. I really do feel as if I’m coming up and the last few days have been evidence of that.

“I had a bad day in the Pyrenees about a week ago but hopefully I’m on track to be at my best in the last week.”

Froome lost yellow on stage 12 to Peyragudes on Thursday but reclaimed it 48 hours later.

However, he had to be at his best just to retain it on Sunday as a broken spoke on his bike left him a minute down on his rivals at the foot of the Col de Peyra Taillade, and the 32-year-old had to go into the red just to save the day as Bardet’s AG2R La Mondiale team drove the race on.

The route for this year’s Tour is a big part of the reason everything is so close. There are only three summit finishes and very few time trial kilometres.

Battles against the clock tend to favour Froome, but he will not be lulled into relying on the time trial to claw back time knowing that Uran poses a strong threat.

“Rigoberto is more the dark horse,” Froome said when asked about his main rivals. “He’s probably the strongest time trialist of this group of GC contenders.”

This might be as close as the Tour has ever been at this stage, but Froome insisted he was not surprised to see the race like it is given how few opportunities this year’s route presents.

“We knew coming into to this year’s race it was going to be one of the closest fought battles and one of the biggest challenges of my career,” he said.