Tour de France favourite Floyd Landis took over the yellow jersey after joining a three-man breakaway on the eleventh stage of the race.
The American finished third behind Denis Menchov who pipped Levi Leipheimer with France's Cyril Dessel missing out on retaining the race leadership by eight seconds.
Menchov's victory in the first mountain finish of the Tour, a 206.5km route from Tarres to Pla-de-Beret in Spain, left him third overall.
The stage included the legendary 18.3km Col du Tour-malet, which has been a Tour regular since its first appear-ance in 1910, as well as four category one climbs.
Landis, who will undergo hip replacement surgery after the race, said he was thrilled to become the new overall leader. "I couldn't be happier," he said. "I didn't want to do all the work but I didn't really have a choice."
David de la Fuente holds the polka-dot jersey, 18 points ahead of Dessel, after dominating the day's climbs and winning the second of the two sprint stages.
Robbie McEwen leads Tom Boonen by 29 points in the battle for the green jersey after beating Gert Steegmans to win the first sprint.
De la Fuente then broke along with fellow Spaniard Iker Camano 31 kilometres in.
They were soon joined by Fabian Wegmann and Juan Antonio Flecha in the lead group while the peloton was being pushed by Dessel's AG2R team. De la Fuente was the first over the summit of the Tourmalet while Wegmann pipped him over the Col d'Aspin.
Camano quickly fell away and De la Fuente then returned to the front over both the Cols de Peyresourde and du Portillon, with last year's King of the Mountains Mickael Rasmussen and Michael Boogerd also high among the points.
Landis and Leipheimer began to make their move towards the top of the Col du Portillon and soon after Menchov joined his Rabobank team-mates, Boogerd and Rasmussen, at the front of the chase group.
The leading trio were caught with 23km remaining and with 10km to go there was a leading group of seven -Christophe Moreau, Carlos Sastre, Andreas Kloden, Evans and the top three finishers.
Leipheimer, Landis and Menchov broke with 3km remaining. Although Leipheimer tried to sprint clear with 500 metres to go, Menchov came back to take the win.