Katusha gained their first win of the 2016 Vuelta a España as Sergey Lagutin conquered the steep mountain at the end of the stage, on which the general classification favourites battled it out.
The breakaway was allowed to contest the stage win, but five minutes behind it was the turn of the peloton's best climbers to try and gain an advantage.
Nairo Quintana (Movistar) was the man who gained the most, attacking Chris Froome and Alberto Contador in the final kilometres of the climb, which regularly exceeded 20 per cent, and gained 25 seconds on his rivals.
Eleven breakaway riders finished ahead of the peloton, having gained an advantage of over 10 minutes by the foot of the only climb in the stage, which came right at the end.
Zico Waeytens (Giant-Alpecin) was the first of the breakaway to attack with 8.5km to go, joined by Gatis Smukulis (Astana) and Jhonatan Restrepo (Katusha).
Restrepo decided to go straight off the front as soon as he caught Waeytens with seven kilometres to go and looked to be racing towards the stage victory
But Restrepo was caught with just 1,500m to go by Perrig Quemeneur (Direct Energie), Axel Domont (Ag2r La Mondiale), Pieter Serry (Etixx-Quick Step) and Lagutin.
Lagutin and Domont were the two remaining to contest the slow sprint to the finish line and it was the 35-year-old Russian rider who took his first Grand Tour stage.
Back down the road, the high pace at the front of the reduced peloton forced race leader Darwin Atapuma (BMC) out the back of the peloton.
At the front, Froome (Team Sky) attacked with Quintana and Contador (Tinkoff) on one of the steep ramps on the ascent, but as he and Contador faded Quintana continued on his charge up the mountain.
By the finish line Quintana had gained 33 seconds over Froome, but it was Contador who found his mojo to sprint past the Sky man and finish 25 behind the Colombian.
Quintana moves into the race lead with an advantage of 19 seconds over his teammate Alejandro Valverde and a gap of 27 seconds over Froome. Atapuma slips to sixth, 1-36 down.
Vuelta a España stage eight, Villalpando - La Camperona (181.5km)
1. Sergey Lagutin (Rus) Katusha, 4-09-30
2. Axel Domont (Fra) Ag2r La Mondiale, at 10s
3. Perrig Quemeneur (Fra) Direct Energie, at 17s
4. Mattia Cattaneo (Ita) Lampre-Merida, at 24s
5. Pieter Serry (Bel) Etixx-Quick Step, at 40s
6. Jacques Janse van Rensburg (RSA) Dimension Data, at 55s
7. Scott Thwaites (GBr) Bora-Argon 18, at 1-11
8. Gatis Smukulis (Lat) Astana, at 1-30
9. Jhonatan Restrepo (Col) Katusha, st
10. Loic Chetout (Fra) Cofidis, st
General classification after stage eight
1. Nairo Quintana (Col) Movistar, 29-55-54
2. Alejandro Valverde (Esp) Movistar, at 19s
3. Chris Froome (GBr) Team Sky, at 27s
4. Esteban Chaves (Col) Orica-BikeExchange, at 57s
5. Leopold Konig (Cze) Team Sky, at 1-16
6. Darwin Atapuma (Col) BMC, at 1-36
7. Alberto Contador (Esp) Tinkoff, at 1-39
8. Daniel Moreno (Esp) Movistar, at 1-44
9. Gianluca Brambilla (Ita) Etixx-Quick Step, at 1-46
10. Samuel Sanchez (Esp) BMC, st
