Primoz Roglic held on to La Roja but saw his Vuelta a Espana lead cut to eight seconds as Michael Storer claimed victory on stage seven.
The first mountain stage of this year's Vuelta promised to shake things up in the general classification pack but two-time defending champion Roglic retained his place in pole position.
However, his lead was trimmed down by 17 seconds in total, with Felix Grossschartner - who finished one minute and 32 seconds behind Storer - closing the gap.
Enric Mas, who was in second, stayed 25 seconds back from Roglic.
The day belonged to Storer, however, with the Team DSM rider powering to victory on the breakaway, finishing 21 seconds clear of Carlos Verona up the Balcon de Alicante, the last of six categorised climbs on Friday.
Storer's aggression paid off with 4km remaining when he countered an attack from Movistar's Verona, who crossed the line 38 seconds ahead of third-placed Pavel Sivakov, who also clinched the lead in the climbers' classification.
Verona's effort capped a difficult day for Movistar, who lost Alejandro Valverde with around 40km of the route remaining.
The Spaniard, who started the day fourth overall, attacked on the Puerto El Colloa, attempting to put his GC rivals onto the back foot, only to spin out of control on a difficult right-hand turn.
Valverde, the 2009 Vuelta champion, crashed through a gap in the barriers and onto the lip of the hillside, though fortunately managed to avoid tumbling over it.
He attempted to carry on after receiving treatment, but could not last and is out of the tour.
1. Michael Storer (Team DSM) 4:10:13
2. Carlos Verona (Movistar) +0:22
3. Pavel Sivakov (INEOS Grenadiers) +0:59
4. Sepp Kuss (Jumbo-Visma) +1:16
5. Jack Haig (Bahrain Victorious) +1:24
1. Primoz Roglic (Jumbo-Visma) 25:18:35
2. Felix Grossschartner (Bora-Hansgrohe) +0:08
3. Enric Mas (Movistar) +0:25
1. Jasper Philipsen (Alpecin-Fenix) 131
2. Fabio Jakobsen (Deceuninck-QuickStep) 130
3. Magnus Cort (EF Education-Nippo) 67
King of the Mountains
1. Pavel Sivakov (INEOS-Grenadiers) 16
2. Michael Storer (Team DSM) 12
3. Jack Haig (Bahrain Victorious) 11
It is back to the flats for stage eight, with a sprint finish into La Manga del Mar Menor rounding off the first week of action.