Portugal's Rui Costa attacked on the final climb of Friday's 204-kilometer (127-mile) trek through the Alps to garner his second stage win of the centennial Tour de France.
Leading his closest competitors by more than 5 minutes, British cyclist Chris Froome remained secure in the yellow jersey with just two more stages left in the race.
Costa, 26, employed the same tactics that he used to win Tuesday's stage: join an early break-away and then rely on a combination of tactics and sheer power to grab the victory.
His Movistar teammate Nairo Quintana continues to sit in third place after Friday's stage, just 21 seconds behind two-time Tour winner Alberto Contador of Spain.
Contador's fellow Saxo-Tinkoff rider Roman Kreuziger and another Spaniard, Joaquim "Purito" Rodriguez of the Katusha team, are also within reach of a spot on the podium in Paris.
The Tour will remain in the Alps for Saturday's penultimate stage, which features an ascent of Semnoz, a beyond-category peak.