Tour de France leader Bradley Wiggins retained the yellow jersey for a 10th day after surviving repeated attacks on stage 16 in the Pyrenees.
The 197-kilometre route from Pau to Bagneres-de-Luchon was won by Thomas Voeckler (Europcar), but Wiggins moved a step closer to overall victory by repelling attempted assaults from Vincenzo Nibali.
Nibali (Liquigas-Cannondale) began the day two minutes 23 seconds behind and accelerated away from Wiggins on the day's fourth and final climb, the Col de Peyresourde, the top of which came 15.5km from the end of the stage.
But Wiggins, with support from Team Sky colleague Chris Froome, kept the Italian within sight and reeled him in, and the trio finished 7mins 9secs behind Voeckler.
Wiggins retained a 2:05 lead over Froome, with Nibali 18 seconds further adrift.
The Italian appears to be the only realistic challenger to a Team Sky and British victory.
Defending champion Cadel Evans (BMC Racing) began the day 3:19 behind, but struggled going uphill and was cast adrift as Wiggins moved within four days of top spot on the Paris podium, with tomorrow's 143.5km 17th stage from Bagneres-de-Luchon to the summit at Peyragudes the biggest obstacle to a first British Tour triumph.
An early escape featured 38 riders - the best placed overall being Spain's Egoi Martinez (Euskaltel-Euskadi), who began the day more than 18 minutes behind Wiggins.
Voeckler led over the summit of the Col d'Aubisque before Irishman Dan Martin (Garmin-Sharp) initiated the move which saw the breakaway group disintegrate on the lower ramps of the 19km ascent of the Col du Tourmalet, the day's second hors categorie (beyond category) climb.
French duo Brice Feillu (Saur-Sojasun) and Voeckler then attacked alone with the summit in sight, as six Team Sky riders led the peloton, almost 10 minutes behind.
Voeckler and Feillu continued to forge on together up the Col d'Aspin, the day's penultimate categorised climb, a 12.4km category one ascent.
Seven others - Martin, Hincapie, Jens Voigt (RadioShack-Nissan-Trek), Alexandre Vinokourov (Astana), Laurens Ten Dam (Rabobank) and Chris Anker Sorensen (Saxo Bank-Tinkoff) and Vasili Kiryienka (Movistar) - were in pursuit as the remnants of the day's early escape were being caught by the peloton.
Ivan Basso moved to the front to increase the pace in support of his team-mate Nibali.
Immediately Evans began to struggle and he was 45 seconds behind the Wiggins and Nibali group going over the summit.
Team Sky had three riders alongside Wiggins, including Froome. Richie Porte and Michael Rogers were also present.
Three BMC Racing team-mates dragged Evans back to the yellow jersey group on the descent and towards the lower slopes of the Col du Peyresourde, while up ahead Voeckler moved to go ahead on his own with 22km to go.
The 9.5km ascent at an average of 6.7%, featured the route's steepest slopes and was ideal for an attack.
Evans again fell back from the yellow jersey group as Liquigas-Cannondale, Lotto-Belisol and Team Sky, with Froome and Porte in support of Wiggins, vied for position at the front of the group.
Nibali accelerated out of the group inside 20km to go, but Froome paced Wiggins behind as they kept the Italian in sight, with the remaining challengers unable to keep pace.
Froome and Wiggins bridged the gap as the trio pushed on towards the summit.
Nibali again went to the front of the group with 500m to go to the top of the climb, with Wiggins following his wheel and Froome one place further back.
The Italian is known for his demon descending but did not attack on the downhill and finished alongside the Team Sky duo on a stage which saw Voeckler solo to victory.
Sorensen was second, 1:40 behind and Gorka Izaguirre (Euskaltel-Euskadi) third, 3:22 adrift.
Wiggins appeared comfortable in the finale, but it was a miserable day for Evans.