Barguil is the first French rider to win a Tour stage on Bastille Day - France's national day - since David Moncoutie in 2005.
Froome's teammates had set a fast tempo that prevented others from attacking - a tactic that prepared the ground for Froome's expected assault in the steep final section leading to the finish in the ski station of Peyragudes.
Frenchman Romain Bardet, runner-up past year, won the stage to stay third overall, 25 seconds behind Aru, while Froome slipped to second, six seconds off the pace.
"If you look at the other Tours (Froome won), he always won the first stage in the Pyrenees", said the Kazakh, a former victor of the Vuelta when a rider, although he later served a doping suspension.More news: Shiny Tapu Koko is Available Now for Pokemon Sun and Moon Players
Not today. Stage 12 of the Tour finished with a pair of climbs in rapid succession, and through the first, it was business as usual.
"There's been so many kilometres already this race and they might be flat stages, but it's still time on the bike". He has an 18 second-lead over Aru, with Bardet 51 seconds off the pace. But the Brit surrendered his yellow jersey on Thursday when he lost over 20 seconds in the final 300 meters to Fabio Aru. The Team Sky rider has never not been in the yellow jersey this late in any of the three Tours he won. Overall, Froome is a mere six seconds behind Aru and bookmakers remain confident that the British cyclist will triumph. It's as simple as that - I just didn't have the legs on the final kick. In 2014 as leader of Team Sky (after Froome's withdrawal) he was struck down with pneumonia, and in 2016 a puncture at a crucial stage early on marred his chances.
"It was actually a great feeling to go out there and race for the win, " Froome said.
Landa finished fourth behind Contador and Colombian Nairo Quintana, who is back in contention in eighth place overall, 2:07 behind Aru."Beating Contador is something huge for me because he's always been my idol", said Barguil.More news: Jose Mourinho: 'Zlatan Ibrahimovic could sign new Manchester United deal'
"I thought, 'Oof. That was close, '" Kittel said of Bodnar's effort.
The short stage 13 was tipped as potentially crucial in the battle for the overall victory, with three mountain passes opening the possibility for attacks.
Quintana zoomed over the line in second place, failing to catch Barguil with his final sprint, with Contador third.
Friday, the 13th step compact difficulties by 101 kilometres between Saint-Girons and Foix. He was hoping that him following me would make me not want to go in the breakaway but it made me want to go in it more.More news: Wimbledon: Sania Mirza crashes out, Bopanna advances to mixed doubles quarters
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