Chris Froome was unable to keep pace with his main rivals on a brutal climax to the 15th stage of the Vuelta a Espana.
Froome was well positioned as the peloton began the hors-categorie climb up to the Lagos de Covadonga, but couldn't react as Alberto Contador, Joaquim Rodriguez and Alejandro Valverde surged up the road in the final five kilometres.
The Tour de France runner-up continued to dig deep as he battled towards the finish, and with Rigoberto Uran and Sergio Henao both fighting his corner, managed to limit his losses to 35 seconds as he crossed the line in 23rd position.
That result saw Froome drop one place to fourth in the overall standings, where he now sits 2min 16sec behind red jersey holder Rodriguez (Katusha). Contador (Saxo Bank - Tinkoff Bank) remains in second, 22 seconds off the pace, with Valverde (Movistar) a further 1min 19sec adrift in third.
The stage itself had a surprise winner with Caja Rural rider Antonio Piedra attacking solo from a 10-man escape group on the foot of the final climb and the Spaniard clung on to seal the biggest victory of his career by a 2min 02sec margin.
Fellow breakaway incumbents Rubén Pérez (Euskaltel) and Lloyd Mondory (AG2R) also stayed clear to seal second and third places respectively.
Immediately after the stage, Froome gave an honest assessment of his performance, and said: “It was a really tough climb today and I was definitely suffering out there.
“I’m struggling against the Spanish riders in the mountains at the moment but I’m still trying to do as much as I can to stay up there.
“I’m not sure where I’m going to end up but I’m going to keep giving the maximum effort possible, and if I can do that, I’ll be happy.”
1 Antonio Piedra Perez (Spa) Caja Rural 5:01:23
2 Ruben Perez Moreno (Spa) Euskaltel - Euskadi 0:02:02
3 Lloyd Mondory (Fra) AG2R La Mondiale
4 David De La Fuente Rasilla (Spa) Caja Rural
5 Pablo Lastras Garcia (Spa) Movistar Team 0:02:07
6 Simon Geschke (Ger) Argos-Shimano 0:02:12
7 Kevin Seeldraeyers (Bel) Astana Pro Team 0:02:25
8 Andrey Kashechkin (Kaz) Astana Pro Team 0:03:35
9 Vicente Reynes Mimo (Spa) Lotto Belisol Team 0:03:49
10 Sergey Lagutin (Uzb) Vacansoleil-Dcm Pro Cycling Team 0:06:45
23 Christopher Froome (GBr) Sky Procycling
130 Ben Swift (GBr) Sky Procycling
133 Ian Stannard (GBr) Sky Procycling
167 Stephen Cummings (GBr) BMC Racing Team
General classification after stage 15
1 Joaquim Rodriguez Oliver (Spa) Katusha Team 58:17:21
2 Alberto Contador Velasco (Spa) Saxo Bank - Tinkoff Bank 0:00:22
3 Alejandro Valverde Belmonte (Spa) Movistar Team 0:01:41
4 Christopher Froome (GBr) Sky Procycling 0:02:16
5 Daniel Moreno Fernandez (Spa) Katusha Team 0:04:51
6 Robert Gesink (Ned) Rabobank Cycling Team 0:05:42
7 Andrew Talansky (USA) Garmin - Sharp 0:06:48
8 Laurens Ten Dam (Ned) Rabobank Cycling Team 0:07:17
9 Nicolas Roche (Irl) AG2R La Mondiale 0:07:21
10 Igor Anton (Spa) Euskaltel - Euskadi 0:07:39
139 Ian Stannard (GBr) Sky Procycling 1:55:53
157 Stephen Cummings (GBr) BMC Racing Team 2:06:25
161 Ben Swift (GBr) Sky Procycling 2:08:01