Ireland's Dan Martin moved up three places to seventh on general classificiation on a day when Poland's Przemyslaw Niemiec won the 15th stage of the Vuelta a Espana and Alberto Contador moved further ahead of Britain's Chris Froome at the end of a gruelling final ascent into Lagos de Covadonga .

Spaniard Contador, who retained the overall leader's red jersey, battled against the negative tactics of Alejandro Valverde and Joaquim Rodriguez to finish a few seconds behind his two compatriots.

The Saxo-Tinkoff rider attacked time and again in the final climb a 12.2-km ascent at an average gradient of 7.2 per cent.

But Rodriguez and Valverde refused to co-operate to get rid of Froome, who was struggling a few metres behind.

The Briton limited the damage and still lies third overall, 1.20 behind Contador after losing seven seconds to the Spaniard at the end of Sunday’s 152.2-km ride.

Martin came home in seventh spot, 28 seconds behind Niemiec to move up to seventh, four minutes and 55 seconds behind Contador.

Frenchman Warren Barguil was the first to shake off a small group of favourites in the final climb but it was Contador who went hard in the final six kilometres.

Froome, who was yo-yoing at the back, appeared to crack several times but always managed to fight his way back, never losing sight of Contador.

The double Tour de France champion, looking to win the Vuelta for the third time, was outsprinted by Valverde and Rodriguez in the finale as the Movistar and Katusha riders snatched six and four seconds of time bonuses respectively.

Niemiec, of the Lampre-Merida team, was the sole survivor of the day’s breakaway and held off the trio of rivals to win the stage, crossing the line five seconds ahead of Valverde and Rodriguez.