With a big, 19-man breakaway going clear on the early climbs, some very talented riders were up ahead of the bunch including Wout van Aert, Sergio Higuita,
Rui Costa, Marc Hirschi, Neilson Powless, winner of the stage 1 time-trial Stefan Kung and best placed in the GC, Gorka Izagirre.
As the break began to ascend the final climb of the day, things began to split up. With groups split across the road, a select group was upfront.
Proving to be the strongest climbers in the break were
Antonio Tiberi, Powless and Costa with the trio dropping all their rivals.
Back down the road, the GC battle began to ignite. Felix Gall attacking with only an elite handful able to follow him. Missing from that group were both Remco Evenepoel and Mattias Skjelmose.
As Juan Ayuso attacked from the Gall group the time gap to the leaders dropped under a minute with the trio up front beginning to get tetchy and trying to break free from each other.
Soon, Ayuso hit the front and immediately came around, setting about riding clear solo.
Reaching the top of the climb, Ayuso had a 33 second advantage over Costa and Tiberi with the race leader Gall 1:03 down on Ayuso, meaning the Yellow Jersey was very much in play.
Further back again, Evenepoel had been dropped from a group with Skjelmose that was chasing to catch the Gall group.
Knowing he could move into the race lead, Ayuso was taking risks on the descent, hitting 100kmph according to one of the camera bikes.
After securing the stage win, the clock started ticking with Ayuso knowing he needed to make up the 1:18 deficit he started the day with.