Strong field threatens Froome's Tour-Vuelta double dream

Chris Froome will face a star-studded field led by Colombian Nairo Quintana as he aims to become just the third rider to win the Tour de France and the Vuelta a Espana in the same year.

Indeed, defending champion Alberto Contador is the only one of the top five from this year's Tour de France not to take part in the gruelling three-week tour around Spain as former Grand Tour winners Vincenzo Nibali and Quintana's Movistar teammate Alejandro Valverde also eye victory in Madrid come September 13.

A late surge by Quintana couldn't prevent Froome from claiming the second Tour de France title of his career last month and the Briton will be backed by another strong Team Sky line-up as he attempts to win the Vuelta for the first time after runners-up finishes in 2012 and 2014.

Frenchmen Jacques Anquetil (1963) and Bernard Hinault (1978) are the only riders to have previously won both the Tour de France and the Vuelta in the same year.

"I have great memories from this race so I'm pleased to be back. I've had a good rest after the Tour and now I'm ready for my next challenge," said Froome.

"It will certainly be a very competitive race given the strong field -? which will be great for the fans to watch. The competition will be tough and this is bike racing so anything can happen, but we have an excellent team and we?re ready to get the race started."

Movistar's dual star strategy of including both Quintana and Valverde was criticised during the Tour despite both making the podium as the former's relentless attacks on the final two stages couldn't compensate for the time he lost in the first week.

However, Movistar team manager Eusebio Unzue defended the decision to once again not name an outright leader of the team.

"They have both had successful seasons and completed their programmes without any unforseen problems," he said.

"There is always a pressure that exists to do well, but we hope to get to every stage in good condition and they are both preparing for the Vuelta with a lot of excitement."

Nibali also got stronger at the Tour progressed to finish fourth and went head-to-head with Froome on a couple of occasions with the Sky man declaring the Italian "unsportsmanlike" for an attack as Froome suffered a mechanical problem.

The 2014 Tour de France champions forms part of what team manager Giuseppe Martinelli has described as the "strongest ever" Astana team which also includes Fabio Aru and Mikel Landa, who finished second and third respectively in the Giro d'Italia earlier this year.

American Tejay Van Garderen could also figure in the fight for the general classification as he returns after having to withdraw from the Tour de France when lying third in the standings due to headaches.

The race gets underway with a team time trial from Puerto Banus to Marbella on Saturday.

Thereafter, there are eight mountain finishes to favour the better climbers, but a 39km individual time trial in Burgos in the final week could hold the key to victory.

The final stage will return to its traditional procession around the streets of Madrid after a final stage time trial in Santiago de Compostela last year to mark the 800th anniversary of St Francis of Assisi's visit to the city.