Next year Chris Froome will face many of the same rivals that he were up against in this year's Tour de France but Vincenzo Nibali will be an important addition to the list of overall contenders. Team Sky principal David Brailsford points to the Giro champion as Froome's biggest rival.

In 2010, Vincenzo Nibali was close to signing a contract with Sky but chose to stay at his Liquigas team for another couple of years before joining Astana for this season. Clearly admiring the Giro champion, Sky principal David Brailsford has now pointed the Italian as Chris Froome's biggest rival in next year's Tour de France.

Nibali won the Giro d'Italia in superior fashion earlier this year and went on to finish 2nd at the Vuelta a Espana. He was arguably the strongest rider in the world championships where he came back from a crash to finish 4th on the tough course in Florence.

Nibali was the biggest Sky rival when he last raced the Tour in 2012 and finished 2nd behind Bradley Wiggins and Chris Froome. Next year he will once again target the world's biggest bike race and despite the likely presence of riders like Nairo Quintana and Alberto Contador, Brailsford has singled out Nibali as the man that may beat the seemingly invincible Froome.

"Nibali is our main rival," he told Gazzetta dello Sport. "I've no doubts about that after seeing the route of next year's Tour de France."

Nibali is known as an aggressive racer that goes on the attack even in less favourable terrain. In 2013, he is the only rider who has beaten Froome in a direct battle in a stage race when he disposed the Brit from the lead by a courageous attack on the epic penultimate stage of the Tirreno-Adriatico.

That stage was not a typical mountain stage and not expected to produce too much separation among the GC riders. The ability to attack when it is least expected, is what Brailsford fears the most.

"The thing I like about Vincenzo is that he's a real racer," he said. "He's a fighter, he's aggressive and never gives up. He can transform a stage into a trap, he's creative and courageous."

Brailsford sees the inclusion of cobbles on the Tour route as an advantage for Nibali.

"He always gives 100%," he said. "You can see his talented and has a modern way of racing. Just think what he can do on the difficult stages and there are a lot of them. On the pave where he's definitely better than Froome. I've seen him ride on the dirt roads at the Giro and then look how good he is on the bike on the descents when it rains."

On paper, Froome is the superior time trialist of the two but with the only time trial coming on the penultimate day, Nibali may be able to limit his losses.

"Nibali is the most complete of Chris' rivals," Brailsford said. "He could take advantage of the position of the only time trial because it's on the penultimate day."

"The race tactics will change completely and mountain stages will be talked differently. You can't wait too much, you'll have to take risks. It'll produce an aggressive race that will be spectacular for who watches it and so excellent for our sport."

Many have pointed to the limited amount of time trialing as a disadvantage for Froome but Brailsford insists that his captain is first and foremost a climber. Froome won two mountain stages in this year's Tour de France.

"I've always believed that Chris is much more of a climber than a time trialist and so he's got to gain time in the mountains," he said. "That will be his mission, without waiting for the time trial. It'd be too risky to put everything on one day. There are five mountain finishes and Froome certainly isn't penalised by that."

2012 champion Wiggins has indicated that he would like to go back to the Tour one final time to support Froome. According to Brailsford, nothing has, however, been decided yet.

"We haven’t decided yet," he said. "The Giro d'Italia? It's unlikely but I won’t exclude it. The Tour with Froome? We'll be starting at home and so I'd like that all the British riders are in the team and Wiggins is one of them. But when you decide a team you don’t look at riders' passports or nationality. The goal is to win and that's it."

The Tour starts on July 5 in Leeds.