197 riders started at 13:33. Nineteen riders broke clear in the first ascent of the day, the third category Alto de Capella, including red jersey holder Ruben Fernandez, forcing Team Sky to chase to close the gap. Thomas De Gendt (Lotto-Soudal) was first at the top ahead of Egor Silin (Katusha) and Pierre Rolland(Cannondale) and the Belgian went on in the descent. He was rapidly joined by twenty other riders: Darwin Atapuma (BMC), Enrico Battaglin (Lotto NL-Jumbo), Andrey Zeits (Astana), Nikias Arndt and Chad Haga (Giant-Alpecin), Axel Domont (AG2R-La Mondiale), Zdenek Stybar (Etixx-Quick Step), Benjamin King and Pierre Rolland (Cannondale-Drapac), Nathan Haas and Merhawi Kudus (Dimension Data), Lawrence Warbasse and Marcel Wyss (IAM Cycling), Tsgabu Grmay (Lampre-Merida), Stephane Rossetto (Cofidis), Cesare Benedetti and Scott Thwaites (Bora-Argon18), Angel Madrazo and Jaime Roson (Caja Rural-Seguros RGA), Lilian Calmejane (Direct Energie). Their lead reached 1:55 at kilometer 50.
The race lost two more riders: Vicente Reyes (IAM Cycling) and Federico Zurlo (Lampre-Merida) at that stage.
De Gendt again collected the points at the top of the second climb of the stage, Alto Monte Caxado (Km 58.3), ahead of Domont and Madrazo. The gap reached 4:45 with 70 km to go over a bunch constantly led by Fernandez's Movistar team-mates. It went up to 5:30 in the last 25 kilometers when De Gendt, Stybar, Grmay and twice Domont tried to attack in turn. The young AG2R rider found himself on his own with 12 km to go as Tinkoff toot the reins of the peloton but he was caught in the finale as Calmejane tackled the last ascent in the lead, followed by Rolland. The peloton was then 3:30 behind.
In his first year as a professional, Calmejane widened the gap with his former companions in the last ascent and saved enough strength to earn a deserved victory in his first pro season. Behind him, Atapuma sprinted ahead of Ben King to go for second place and become the fourth Vuelta leader in four days with a 29 seconds lead over Valverde and 33 ahead of Chris Froome.
