Tomasz Marczynski (Lotto Soudal) picked up a second stage win in this year's Vuelta a España by coasting to victory in stage 12 with a gap of 52 seconds, while Chris Froome (Sky) saw his overall lead reduced by 20 seconds after enduring a messy finale.
"It was an incredible stage," Marczynski said. "After my first victory, I was keeping fresh to try again today. I was a bit afraid at the beginning - I spent a lot of energy and had to sprint like 100 times just to get in the breakaway.
"Once I was there I said 'today can be again my day'. I felt good from the beginning, I was climbing easy. I kept calm until the last climb and there I wanted to see how the others were doing, and when I saw I had good legs I tried to go alone."
The Vuelta race leader had a mechanical issue with around 8km remaining in the 160km stage from Motril to Antequera Los Dolmones and was forced to change bikes. Moments later he crashed on a bend and recovered to finish 52 seconds behind Alberto Contador (Trek-Segafredo), who finished strongest of the general classification group.
Froome lost 20 seconds on nearest challenger Vincenzo Nibali, but still holds onto the red jersey with a lead of 59 seconds on the Bahrain-Merida team leader, who will look to take advantage of having fresher legs than the Tour de France winner in the final week of La Vuelta after sitting out the Tour.
Contador, who will retire after La Vuelta, continued to show he is not ready to bow out quietly and attacked from the peloton with 20km to go alongside Nicolas Roche (BMC) and opened up a 10-second lead, eventually finishing 22 seconds ahead of stage 11 winner Miguel Angel Lopez (Astana).