Roglic had little trouble responding to the attacks by his rivals over the 190-kilometer (118-mile) ride with five categorized climbs from Arenas de San Pedro to a summit finish at Plataforma de los Gredos in the mountains west of Madrid.
As is custom at the three-week grand tours, riders respect the leader and do not attack on the 21st and final stage. So barring an accident or some unlikely mishap, Sunday's arrival to Madrid will be a relaxed jaunt for Roglic and his yellow-clad Jumbo-Visma teammates to celebrate the title.
The Slovenian, who turned to cycling after giving up on his first sport of ski jumping in 2012, leads world champion Alejandro Valverde by over 2 1/2 minutes heading to the final day. Roglic said despite a couple of crashes and the strong winds on Stage 17 that challenger Nairo Quintana used to get back in contention, he never feared for his lead.
"For sure it was not the easiest Vuelta," he said. "But I had a strong team around me and we managed to keep everything in control." He said his next goal could be a shot at the Tour de France. "Why not?" he said.
Fellow Slovenian Tadej Pogacar confirmed he is the surprise of the race by pulling off a long solo attack to win the stage in just over five hours, moving him into third place overall. It was the 20-year-old Pogacar's third win of the race.
"It's really incredible. I don't think I was ever imagining this, but I think I will need a few days to understand it," Pogacar, who rides for UAE Team Emirates, said. "I felt good on the long last climb. I chose the right moment and went full gas to the finish."
Roglic showed his promise when he was fourth in the 2018 Tour de France and third in the Giro d'Italia in June, where he also won two stages. He has excellent time trialing skills and the ability to also perform well in the toughest mountains.
Roglic took control of the Vuelta and dealt a heavy blow to his rivals on the Stage 10 time trial, where he built an almost two-minute lead over Valverde. That proved enough. Despite the best efforts of Valverde's Movistar team and Miguel Ángel López's Astana, Roglic defended the red jersey with aplomb through the most grueling mountains in northern Spain.
That included Saturday's trek through rain and cold temperatures. Roglic was left alone after the hard pace set by Astana that shed the other Jumbo-Visma riders, but he matched López's charges and a late push by Valverde.
The 39-year-old Valverde protected his second place on the podium after racing hard up the final ascent to finish behind Pogacar, who knocked Quintana off the podium in his final race for Movistar. Valverde won the Vuelta in 2009.
"I am very satisfied," said Valverde, who is 10 years older than Roglic. "I didn't dream of a second place." Sunday's final stage is a flat 106 kilometers (65 miles) from Fuenlabrada to the Spanish capital.
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