Ireland's Eddie Dunbar (Team Jayco AlUla) hung on to win a punishing stage 20 of the Vuelta a Espana on Saturday, with three-times former champion Primoz Roglic coming in third and extending his overall lead.

The Slovenian now has an overall lead of two minutes and two seconds over Australia's Ben O'Connor, whose heroic resistance in hanging on to the red jersey was finally broken on stage 19.

Dunbar, who also won stage 11, took off in pursuit of the leader Pavel Sivakov with five kilometres to the finish on the final climb of this year's Vuelta to Picon Blanco and went on to hold off the chasing group after overtaking the Frenchman.

Spain's Enric Mas (Movistar) came in second with Roglic, who took control of the red jersey after winning Friday's stage, close behind.

The 172km ride from Villarcayo contained seven categorised climbs to test the riders on the penultimate stage, and it was the Irishman who proved strongest, while Roglic (Red Bull-Bora-Hansgrohe) did all that was needed to strengthen his grip on the red jersey.

Dunbar, who has struggled with crashes and injuries in recent times, made his break from a small group of riders containing the top five in the general classification.

"I knew this climb from a few years ago and knew there were steep bits and parts where it levelled out, and that it was a bit different to what was shown on the profile," Dunbar said.

Roglic, who won three consecutive Vueltas from 2019, came into this year's race as clear favourite, with the likes of Tadej Pogacar, Jonas Vingegaard and Remco Evenepoel all opting not to ride in Spain, but he had risked losing out to O'Connor.

O'Connor (Decathlon-AG2R La Mondiale) took the red jersey from Roglic after winning stage six, opening up a gap of almost five minutes, but the Slovenian slowly chipped away at the lead, and seized control in style when winning Friday's stage.

Sunday's final stage is a 24.6km individual time trial in Madrid, where Roglic is set to be crowned champion for the fourth time. Mas is third overall, nine seconds down on O'Connor.

"Definitely one day closer than yesterday, so the right direction, but tomorrow is a GC day so we have to finish it off," Roglic said.