Italy's Vincenzo Nibali will bid for a second Grand Tour success of 2013 when he begins the Vuelta a Espana on Saturday.
The Astana rider prevailed through inclement weather to win May's Giro d'Italia and will hope success in the year's third and final Grand Tour can act as a major boost ahead of next month's Road World Championships in Florence, where he will start as one of the favourites in the road race.
Nibali, who was third in the 2012 Tour de France behind Bradley Wiggins and Chris Froome, missed the 100th edition of the race to focus on the Giro.
With the pink jersey won, now the target is the Tour of Spain's red jersey - and his Astana sporting director Alexandre Vinokourov believes the Italian is capable of victory in the three-week race, which begins in north-west Spain.
Vinokourov, the 2006 Vuelta winner and 2012 Olympic road race champion, said on proteam-astana.com: "I think he can win as his form and condition develop during the race. After 10 stages Nibali will be 100 per cent."
Nibali will face competition from Alejandro Valverde (Movistar), Joaquim Rodriguez (Katusha), Ivan Basso (Cannondale), Dan Martin (Garmin-Sharp) and Belkin duo Bauke Mollema and Laurens ten Dam for the red jersey in a race Vinokourov predicts will be every bit as challenging as the Giro and Tour.
The controversial Kazakh, who served a two-year ban for blood doping after being kicked out of the 2007 Tour, added: "It would be tough to find weather conditions more difficult than this year at the Giro, but overall the Vuelta will be no less of a challenge. Maybe even harder.
"And the Tour is of course a more popular race, but maybe this year the Vuelta will be even harder."
The 3,359-kilometre Tour of Spain will take an anti-clockwise route from Saturday's start - a 27.4km team time-trial from Vilanova de Arousa to Sanxenxo - before finishing in Madrid on 15 September.
Of the 21 racing days, 13 are considered mountain days, which include the penultimate stage to the summit of the Angliru, a day where the race winner will be decided.
In 2011, Jose Cobo effectively sealed victory by dropping Team Sky riders Froome and Wiggins on the climb.
Colombian Sergio Henao will lead Team Sky's challenge on this occasion after Froome's Tour de France triumph.
With defending champion Alberto Contador absent, Spanish hopes will rest on Valverde, the 2012 runner-up and 2009 winner, and Rodriguez.
A number of riders will be using the Vuelta to find form for the World Championships in Tuscany on 28 September, including world road race champion Philippe Gilbert (BMC Racing) of Belgium.
Gilbert crashed at the Eneco Tour last week but is still expected to start.