Sprinboarding from the breakaway, Quintana proved he's far from a spent force at this year's Tour, holding off a charging Romain Bardet (AG2R La Mondiale) and putting five minutes into his GC rivals. The Colombian now sits seventh on GC.
"It's a reflection of all the work we have done," said Movistar's Quintana. "I have worked a lot since the beginning of the Tour to get here."
"This stage was one for the pure climbers, for the real climbers in the bunch, and I was present. I was ready for it. It's a beautiful win, and on a stage like this, with this type of profile, it makes me emotional."
On a hot day in the valleys and peaks of the French Alps, a big battle unfolded to make the breakaway as many riders hoped to contest the 208 kilometre stage.
[tdf widget="stagewinners" stage="18"]
Alexey Lutsenko (Astana) was the best of the early aggressors, but the Kazakh waited for others to form a more workable early move. Attacks flurried from the peloton until the move was finally established with 34 riders escaping up the road. Foremost among them in the battle for the general classification was Quintana, starting the stage nine and a half minutes down on yellow jersey Julian Alaphilippe (Deceuninck-QuickStep).
Defending his polka dot jersey, Tim Wellens (Soudal Lotto) won over the Category 1 climb of the Col de Vars. Greg van Avermaet (CCC) and Julien Bernard (Trek-Segafredo) launched off the front of the group trying to steal a march on the more accomplished climbers of the group, the move earning Van Avermaet the stage's combativity prize.
Deceuninck-QuickStep set themselves to chasing duties on the front of the peloton, dragging the main group until Movistar hit the front of the peloton on the lower slopes of the Col d'Izoard. Movistar's pressure immediately splintered the peloton, dropping riders high on the general classification like Dan Martin (UAE Team Emirates) and Romain Kreuziger (Dimension Data).
A long turn on the front by Marc Soler (Movistar) diminished the peloton to just 17 riders, with most key domestiques for the GC riders eliminated. Van Avermaet then Bernard were swept up by the chasers from the initial breakaway as they reached the summit of the Col d'Izoard.
Quintana attacked 26 kilometres from the finish and despite valiant attempts from Bardet and Lutsenko the Colombian crested Galibier with nearly two minutes advantage, and six minutes on the yellow jersey group.
Bernal made his move 24 kilometres out, quickly building an advantage over the yellow jersey group. Geraint Thomas was next to attack, the other favourites scrambling to respond, but respond they did and ate into Bernal's lead, Ineos' tactics seemingly at odds with each other.
While Alaphilippe was dropped by Ineos' raids and lost 20 seconds, they came too close to the Galibier's summit, the Frenchman easily catching the Thomas group with his trademark descending and still far from fully crumbling.
Ahead, Quintana descended safely, crossing the line ahead of Bardet in second and Lutsenko third, Bardet's efforts earning him the mountains jersey which he hopes to carry to Paris.
In the battle for the yellow jersey, Bernal took 32 seconds, moving to second overall, five seconds ahead of team mate Geraint Thomas. The Colombian went to great pains in this post stage interview to state Thomas gave him the green light to attack and the Welshman was still the leader:
[tdf widget="tourleaders" stage="18"]