Britain's Hugh Carthy claimed the biggest stage win of his career on Sunday at the Vuelta a Espana as Richard Carapaz recovered the overall lead.
Carthy delivered an immense performance on the summit finish of the gruelling Angliru to clinch victory on stage 12 while Carapaz finished fourth to move ahead of Primoz Roglic.
Carapaz's lead is only 10 seconds, with a time trial to come, while Carthy jumps to third overall.
Ireland's Dan Martin dropped to fourth, despite a strong showing that limited the damage.
The top four are now separated by just 35 seconds ahead of a rest day on Monday.
Carthy's victory is his first ever in a Grand Tour and it will be particularly special, coming at the end of the fearsome climb of the Angliru, currently one of cycling's toughest ascents.
"It's a dream come true to win any professional race but to win in a Grand Tour on a mythical climb, it doesn't get any better than that. It's hard to put into words," said Carthy of EF Pro Cycling afterwards.
"I think for the public it's everything they want, a close race heading into a time trial. It's everything to play for."
Carapaz of Ineos dug deep to take 10 seconds off Jumbo-Visma's Roglic, the Slovenian coming in fifth.
Astana's Aleksandr Vlasov was second and Enric Mas of Movistar finished third.
"It was too hard a climb for a sprinter!" Roglic said. "I didn't have the best day but it's OK, I'm happy with it.
"Now we go on with the time trial on Tuesday. It definitely will be a really hard one. I will do my best and let's see after Tuesday."
Roglic ran out of steam on the final climb but will expect to retake the red jersey after Tuesday's time trial.
He was not the only one to suffer as Movistar's Marc Soler sank from sixth to 19th, having surrendered more than 14 minutes on the last ascent.
Mas had been the first to push with 3km left but Carapaz, Vlasov and Carthy chased the Spaniard down, with Martin not far behind.
But as the gradient eased, Carthy struck, powering clear and leaving Carapaz for dead to secure a stunning win.
Riders will be given a rest day in A Coruna on Tuesday. The race resumes on Wednesday with the only time trial of this year's event, a 33.7km track between Muros and the third-category summit of Mirador de Ezaro.