Poland's Rafal Majka claimed his second victory of the 2014 Tour de France on stage 17 as Vincenzo Nibali further enhanced his hold on the race leader's yellow jersey.
The 124.5-kilometre route from Saint-Gaudens to Saint-Lary Pla d'Adet was a brute, with four categorised climbs including the finishing ascent where the stage result was decided.
Majka won Saturday's 14th stage to Risoul and recorded Tinkoff-Saxo's second successive Pyrenean stage win after Michael Rogers' success on Tuesday as the team's strong performance since losing leader Alberto Contador to injury continued.
Contador began the race as one of the overall favourites, but it appears no-one will challenge Nibali (Astana) for the maillot jaune now.
Nibali finished third on the stage, 46 seconds behind Majka, but crucially enhancing his advantage over his rivals for the top spot on the podium in Paris on Sunday.
Alejandro Valverde (Movistar) is now five minutes 26 seconds behind after finishing 49 seconds behind Nibali on Wednesday.
Thibaut Pinot (FDJ) remains third, six minutes behind Nibali, after finishing 11th, five seconds behind Valverde.
Jean-Christophe Peraud (Ag2r La Mondiale) is eight seconds behind his fellow Frenchman, though, after finishing fourth on the day, alongside Nibali.
Pinot and Peraud are battling to be the first Frenchman on the Tour podium in 17 years.
The first hour of racing was frenetic, covering more than 50km, as King of the Mountains contender Joaquim Rodriguez missed the eight-rider breakaway.
Rodriguez's Katusha team dragged along the peloton, with six riders at the front ensuring the escapees' advantage wavered around the one-minute mark.
The Spaniard made his move on the first of the day's four categorised climbs, the category one Col du Portillon, cresting the summit first to reclaim the King of the Mountains classification lead from Majka, who began the day in the polka dot jersey.
It was to be the sub-plot on a day which featured two further category one climbs and the hors categorie (beyond category) finishing ascent.
A lead group of 22 riders passed through Tuesday's stage finish town of Bagneres-de-Luchon and Team Sky's Vasil Kiryienka then launched a lone bid, riding on solo with 55km to go on the approach to the Col de Peyresourde.
Kiryienka was reeled in on the penultimate climb of the day, the Col de Val Louron-Azet, with the summit in sight.
There were four leaders at the foot of Pla d'Adet - Pierre Rolland (Europcar), Giovanni Visconti (Movistar), Amael Moinard (BMC) and Nicolas Roche (Tinkoff-Saxo).
Visconti attacked with 9km to go as behind him Romain Bardet (Ag2r La Mondiale) burst clear of the yellow jersey group in an attempt to recoup some of the time lost on Tuesday's 16th stage.
Majka bridged the gap to Roche, Moinard and Rolland, losing Rodriguez, and then continued his burst.
Behind them Valverde was floundering and his podium rivals sensed the weakness and forged on.
Nibali showed his strength by swiftly making ground on the remnants of the day's breakaway.
Up ahead Majka, who curiously pushed off a media motorbike on the final climb in a move which could lead to punishment from race officials, caught Visconti and accelerated on his own with 2.5km remaining.
Majka was able to celebrate another win, with Visconti second and Nibali third as his advantage improved over Valverde.
Valverde recovered on the final ascent to overtake Pinot, with the battle for the podium set to continue in Thursday's 145.5km stage from Pau to Hautacam, although surely now Nibali has the maillot jaune wrapped up.