Chris Froome gave Sky team-mate Nicolas Roche the green light to go for the first summit finish of the Vuelta a España today to Caminito del Rey, safe in the knowledge that would hold his ground with his general classification rivals.
Roche previewed the 4.7-kilometre climb in Spain's south in training, knew every corner and rise, and picked his moment to attack his rivals Esteban Chaves (Orica-GreenEDGE) and Tom Dumoulin (Giant-Alpecin).
His chances of winning the stage, however, were compromised by a mistake.
"I forgot one of the switchbacks. There was a small bit, a drag up, with 500 or 300 to go, then I thought it would flatten out again. It didn't though — it went hard again, and so that was it for me," Roche explained after the finish.
He placed third. Colombian Chaves countered his attack at 500 metres out and held off Dumoulin for the stage win and red leader's jersey.
"When I went, I thought I was going to go there and give it my all. I thought I could do what I did two years ago [to win the stage]. I thought, 'Yeah, cool, I'm in again!'
"In the back of my mind, I thought, I'd give it all and get a gap to hold it. Chaves was very quick to react, and then went straight away and that left me there. When he went, that was it. My card was played."
Nairo Quintana (Movistar), second place at the Tour de France behind Froome, placed 36 seconds back. Froome crossed the line at 40 seconds. Nibali, who chased back after a crash, finished at 1-38 minutes and was later disqualified for holding onto a team car.
The next three stages through the south of Spain are flat. The overall favourites must now hold fire until Thursday, when the sixth stage finishes on a small uphill to Sierra de Cazorla.
"With four kilometres to go, Chris told me, 'Nico, follow the attacks if you want,'" said Roche.
"The big guys can afford to give me or whoever 30 or 40 seconds at this stage in the race. It's an extremely hard Vuelta."
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