Primoz Roglic grabbed back the lead in the Vuelta as he won the 19th stage following a ferocious attack on the final climb on Friday.
The Red Bull-Bora-hansgrohe rider had lost the red jersey on stage six when Ben O'Connor turned a long breakaway into a lead of more than five minutes.
Roglic chipped away at that lead on various mountain finishes and trailed the gritty Australian by only five seconds at the start of Friday's 173.2 kilometre ride through Rioja from Logrono.
The leaders started the closing 8.6km climb to the Alto de Moncalvillo together, but with 6km left, Roglic and two of his teammates blasted off the front.
Dani Martinez set the initial pace. Aleksandr Vlasov briefly took over before their Slovenian team leader zoomed away from both.
He crossed the line 46 seconds ahead of Frenchman David Gaudu of EF Education and Dane Mattias Skjelmose of Lidl.
👑 Roglic reigns supreme! Relive the stage in 1'!
— La Vuelta (@lavuelta) September 6, 2024
❤️ Roglic reina en Moncalvillo... ¡Revive la etapa en 1'!#LaVuelta24 | @gorouvy pic.twitter.com/LPXasXcmmD
O'Connor, of Decathlon AG2R, battled in one minute and 49 seconds behind as his 13 day reign in red came to an end.
"I was a bit broken at the end there," said O'Connor, saying he had expected another Bora attack. "I wasn't surprised but I didn't expect myself to be so bad."
The bonus Roglic gained for winning the stage means he leads O'Connor by 1min 54sec. Spaniard Enric Mas is third a further 26sec back.
After his 15th Vuelta stage win, Roglic is two tough days away from a fourth Vuelta, which would equal the record for most victories held by Spaniard Roberto Heras.
Saturday's stage is another mountain stage, a 172km ride from Villarcayo to Picon Blanco before ending with a 24.6km time trial round Madrid.
O'Connor said he was looking beyond that: "Monday and having beers and sitting on the terrace and relaxing," he said.