Joaquin Rodriguez withstood the attacks of fellow Spaniard Alberto Contador to defend his overall lead on the 15th stage of the Vuelta a Espana.

The stage was won by Caja Rural's Antonio Piedra who escaped a small breakaway group with 10 kilometres to go on the 186.5km stage into Lagos de Covadonga in the Picos de Europa mountains to win in a time of five hours, one minute and 23 seconds.

Ruben Perez of Euskadi-Euskaltel, Lloyd Mondory of Ag2r La Mondiale and Piedra's team-mate David de la Fuente were next, just over two minutes in arrears.

Rodriguez had beaten Contador to the 14th stage win and spent today making sure his rival could not get away in the battle for the leader's red jersey, particularly on the final special category climb at the end of the stage at the summit in Lagos de Covadonga.

In the overall standings Rodriguez remains 22 seconds ahead of Contador, with Alejandro Valverde one minute 41 off the lead and Chris Froome now 2:16 in arrears of Rodriguez.

Ireland's Nicolas Roche finished 30th, 10:55 off Piedra. The Irishman drops from seventh to ninth in the overall standings, 7:21 behind the red jersey.