LA CAMPERONA, Spain (AP) Nairo Quintana successfully attacked Chris Froome on the demanding summit finish of the Spanish Vuelta's eighth stage to take over the lead of the grand tour on Saturday.
Sergey Lagutin of Russia won the 181.5-kilometer (113-mile) stage from Villalpando finishing at the category-one La Camperona summit in just over four hours.
Quintana claimed the red jersey from fellow Colombian Darwin Atapuma, who fell behind the title favorites on the final ascent, which had gradients reaching 25 percent.
Quintana, a Giro d'Italia winner, has twice finished runner-up to Froome at the Tour de France. Froome's supposed challenger at this summer's Tour, Quintana never put the Briton's third Tour title in serious danger.
But Quintana proved he's a rival for Froome at the Vuelta as he stuck with his late charge and dropped Froome over the last few hundred uphill meters.
''Everyone was cautious at the start of the climb, but then Froome went for it, as we expected, and I responded,'' Quintana said. ''I now have that extra bit of confidence knowing that, today, I was a bit better than my rivals.''
Quintana's Movistar teammate, Alejandro Valverde, remained in second place overall, at 19 seconds back, after crossing the line pegged to Froome's wheel.
Froome was third at :27 behind, followed by Esteban Chaves, who fell to almost a minute behind.
Alberto Contador rebounded from his painful crash at the end of Friday's stage by also surging ahead of Froome in the final meters to stay in striking distance at a minute and a half off the pace.
The three-time Vuelta winner made the decision on Saturday morning to keep racing, something that was in doubt after he took a hard knock and scrapes at the end of the seventh stage.
''I am satisfied because the goal was simply to stay alive,'' Contador said. ''I wasn't sure I was going to start the stage. When I could see that I could pass (Froome) at the end I knew I had to take advantage of it.''
Lagutin was a member of an early breakaway of 11 riders who opened up a 10-minute gap over the mostly flat stage that ended in a final 8.5-kilometer (5-mile) ascent.
It was the Katusha rider's first major win.
''Finally the dream came true,'' Lagutin said. ''I have been dreaming of this since I was little, to win a stage at a grand tour. I am 35 years old. At some point I was thinking it was too late.''
Sunday's ninth stage is the second of three consecutive stages in the northern mountains, a 164.5-kilometer (102-mile) ride from Cistierna to the Alto del Naranco.