Contador wins atop Puerto de Ancares to secure Vuelta crown

The Tinkoff-Saxo rider danced clear of Froome (Team Sky) in the closing kilometre of the gruelling 185.7km mountain epic to finally end the Briton's brave effort to turn the tables on his rival.

Contador pointed to his right knee - which he injured badly during the Tour de France - as he crossed the line 16 seconds ahead of Froome. The 31-year-old's second stage victory in a superlative Vuelta sees him extend his overall lead to 1:37.

Alejandro Valverde (Movistar) took third place on the stage, Joaquim Rodriguez (Katusha) fourth and Fabio Aru (Astana) fifth - mirroring the final positions in the general classification ahead of Sunday's short 9.2km individual time trial in Santiago de Compostela.

A quite magnificent final showdown in the mountains always seemed destined for a mano-a-mano battle between the two strongest riders in the race - and Messrs Contador and Froome did not disappoint.

As expected, Froome's well-drilled Sky team set a blistering pace coming onto the final climb of the Puerto de Ancares (12.7km at 8.7%). Froome even drew first blood by picking up two bonus seconds in the intermediate sprint at the foot of the fourth and final categorised climb to cut his deficit to 1:17 in the virtual standings.

But it was Spaniard Rodriguez who made the first move - attacking after lone leader Przemyslaw Niemiec (Lampre-Merida) was reeled in shortly after the steepest 18% section of the climb 9km from the finish.

Rodriguez's attack whittled the chasing group down the the other remaining riders in the top five of the overall standings as Contador, Valverde and Aru were happy to ride in the back wheel of Froome.

His third place on the podium under threat as Rodriguez stretched out a 25-second lead, Valverde edged near the front just as Froome picked up the pace with a trademark seated attack. The acceleration saw both Valverde and Italian youngster Aru drop back.

Froome and Contador caught Rodriguez with 5.5km remaining. Moments after riding with both hands off the bars as he stuffed his sunglasses into his back pocket, Froome launched a devastating attack which cracked Rodriguez.

A resurgent Valverde passed Rodriguez and looked to be returning to the leading duo on the flatter section of the climb 2.5km from the finish. But a series of digs from Froome saw the 2013 Tour de France winner drag Contador further out ahead as the two rode in a pained stalemate towards the finish.

Still without a stage win to his name, Froome put in one last effort in the final kilometre - but Contador danced out of the saddle to deliver the final killer blow and make light of his previously fractured tibia. 

A beaming Contador crossed the line 16 seconds ahead of the grimacing Froome, with Valverde coming home at 57 seconds to secure third place. Rodriguez was fourth at 1:18 with double stage winner Aru taking fifth place three seconds later.

With just Sunday's short ITT remaining, Contador has an unassailable lead of 1:37 over Froome, with Valverde completing the podium at 2:35. Rodriguez is fourth at 3:57 and Aru firth at 4:46. The next rider on GC - Spain's Samuel Sanchez (BMC) - is more than five minutes further of the pace, highlighting the gulf in class between the top five and the rest of the field in this wonderfully exciting 69th edition of the Vuelta.

FOUR-MAN BREAK: Polish climber Niemiec - the stage 15 winner - was joined by Dutchman Wout Poels (Omega Pharma-Quick Step) and Frenchmen Maxime Mederel (Europcar) and Jerome Coppel (Cofidis) in the day's main break.

The quartet built up a maximum lead of 10 minutes before Astana started to ride a fast tempo on the front of the bunch to reduce the gap to six minutes going over the first of four categorised climbs 70km from the finish.

Poels - on the attack for a second day running - was first to fade, the soon-to-be Sky rider caught on the penultimate climb of the day as his future team started to reduce the pack with a devastating pace.

Their jerseys unbuttoned and swaying in the breeze, British national champion Peter Kennaugh and Belorussian Vasil Kiryienka absolutely buried themselves for Froome to reduce the gap to just 45 seconds going over the summit.

By this point, Niemiec had soloed clear of his remaining escapees in a bid to reproduce the effort that saw him ride to victory at Lagos de Covadonga. Both Coppel and Mererel were caught before the start of the Puerto de Ancares climb as Sky continued their bid to break Froome's rivals ahead of the race's final major test.

SANCHEZ AND DEGENKOLB CROWNED: Spaniard Luis Leon Sanchez (Caja Rural) played no huge role in proceedings but the 30-year-old will ride into Santiago in the polka dot mountains jersey after none of his rivals managed to take enough points to topple his tally. 20 points atop the final climb was not enough for Contador to catch Sanchez, who leads his compatriot by 13 points in the KOM standings.

Valverde picked up some green jersey points for his third place - but not enough to reel in Germany's John Degenkolb (Giant-Shimano) who will win the points classification by 23 points to deny the Spaniard a third successive green jersey in Spain.

RIDE OF THE DAY: You cannot fault Team Sky and Chris Froome for their game plan and its execution. Quite simply, they came up against a stronger adversary in Contador, who showed his ruthless streak by giving his British rival no gifts and securing his second stage win - and with it the third Vuelta title of his illustrious career.

DAY TO FORGET: 'Purito' Rodriguez must be applauded for having a pop on the Puerto de Ancares, but his failure to top the podium in the last few weeks means this will be the first year since 2009 that the Spaniard has not picked up a Grand Tour stage win.

COMING UP: Sunday's 9.2km flat time trial in Santiago de Compostela may be something of an anti-climax what with the final podium positions - and top ten - pretty much set in stone. Such is the short distance the time gaps will be minimal. But in the absence of both Tony Martin and Fabian Cancellara it could be a chance for Froome to win his first stage on the race - or for Contador to make it a hat-trick.