Nairo Quintana moved into the red jersey at the Vuelta a Espana after previous leader Alejandro Valverde and Chris Froome both lost time on a rain-soaked ninth stage.
All of the race favourites had been climbing to the summit finish at Aramon Valdelinares together until Alberto Contador blew the group apart with an attack around 2km from the line.
Quintana and Joaquim Rodriguez launched a counter-attack around 500m later and eventually caught Contador to finish on the same time, but both Valverde and Froome were unable to follow and each lost 23 seconds.
The result sees Quintana take over at the top of the general classification, with Contador three seconds adrift in second and Valverde now eight seconds off the pace in third.
Froome falls one place to fifth, 28 seconds back, while fourth place is now occupied by Winner Anacona, who claimed a fine solo victory on the stage after emerging from the day’s breakaway on the final climb.
'Didn't have the legs'
Froome said afterwards: "In the final I didn't have the legs to follow the top guys when they went. But I think given where I have come from on the back of the Tour [de France] and the build-up into the race, I'm really happy with how things have gone so far. I can definitely feel I'm starting to pick up that race rhythm back into my legs and I'm looking forward to the second half of this race.
"I think we have come to see that Contador is going extremely well. He has got over his injuries pretty quickly and he is going well, as are Nairo Quintana and Rodriguez - the usual guys we expected for the general classification. It's a huge fight here and it's going to be a big race all the way to the end. Every second here or there is going to count."
The 185km stage ended with the race’s second summit finish and with potential for a breakaway winner, no fewer than 31 riders made their way into the day’s escape.
Anacona (Lampre-Merida) was the best-placed of them overall, 2min 50sec down on Valverde, and it was no surprise when the Colombian helped to form a new front three with Bob Jungels (Trek Factory Racing) and Javier Moreno (Movistar) on the penultimate climb.
When they took an advantage of almost four and a half minutes on to the final ascent, Anacona sensed taking the red jersey was a possibility and moved into a solo lead with an acceleration 6km from home. The move ensured he won the stage, but events back down the road meant he narrowly missed out on the race lead.
Contador on the attack
Dan Martin (Garmin-Sharp) was the first to attack out of a drastically reduced peloton, and although he was caught a short time later, his burst put Froome (Team Sky) in trouble.
Aware that the Briton had dropped to the back of the group, Contador (Tinkoff-Saxo) launched a ferocious attack and quickly opened up a gap of almost 100m, but then Quintana (Movistar) and Rodriguez (Katusha) responded and, after a long chase, they finally regained parity with the marauding Spaniard just before the line.
Froome and Valverde, meanwhile, were forced to concentrate on limiting losses, and Froome in particular will now look to regain the seconds he shipped in stage ten’s individual time trial on Tuesday.
Froome added: "I'm going to go and see the time trial course tomorrow [Monday's rest day] and see what we are up against. It's relatively short compared to time trials elsewhere. But I enjoy time trialling and I'm hoping to make the most of it."
Quintana said: "I had good legs today and we worked to keep the jersey within this team. Today's stage didn't create big selection and though I'm in the lead, it's almost a goalless draw up to this point. I don't know if we will be able to keep it until the end. It's what we want, but it will be difficult."
Stage nine result
1 Winner Anacona (Col) Lampre-Merida, 4:34:14
2 Alexey Lutsenko (Kaz) Astana, +45
3 Damiano Cunego (Ita) Lampre-Merida, +50
4 Javier Moreno (Spa) Movistar, +1:04
5 Pello Bilbao (Spa) Caja Rural-Seguros RGA, 1:12
6 Jerome Coppel (Fra) Cofidis, 1:21
7 Ryder Hesjedal (Can) Garmin-Sharp, +1:33
8 Adam Hansen (Aus) Lotto Belisol, +1:45
9 Bob Jungels (Lux) Trek Factory Racing, +1:49
10 Fabio Felline (Ita) Trek Factory Racing, +2:08
12 Alberto Contador (Spa) Tinkoff-Saxo, +2:16
13 Joaquim Rodriguez (Spa) Katusha, same time
14 Nairo Quintana (Col) Movistar, st
16 Alejandro Valverde (Spa) Movistar, +2:39
18 Chris Froome (GB) Team Sky, st
1 Nairo Quintana (Col) Movistar, 35:58:05
2 Alberto Contador (Spa) Tinkoff-Saxo, +3
3 Alejandro Valverde (Spa) Movistar, +8
4 Winner Anacona (Col) Lampre-Merida, +9
5 Chris Froome (GB) Team Sky, +28
6 Joaquim Rodriguez (Spa) Katusha, +30
7 Fabio Aru (Ita) Astana, +1:06
8 Robert Gesink (Ned) Belkin, +1:19
9 Rigoberto Uran (Col) Omega Pharma - Quick-Step, +1:26
10 Warren Barguil (Fra) Giant-Shimano, same time