The Colombian, who won the 2016 edition, will leave the Spanish outfit at the end of the season.
He failed to sparkle at the Tour de France, save for a fine solo victory on Stage 18, as he finished 5:30 down on champion and compatriot Egan Bernal (Team Ineos) in the General Classification.
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"We’ll continue with the Vuelta a Espana," Quintana told ESPN on Sunday. "I’ll rest for a little bit in Colombia, then I’ll come back here."
The 29-year-old, also a winner at the 2014 Giro d’Italia, is expected to join French team Arkea-Samsic in 2020.
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Quintana was considered Colombia's best hope to win the Tour before Bernal's emergence and is still targeting the yellow jersey before winding up his career.
"We’ll keep working. I don’t know if one it will happen, but what I do know is that I have to keep fighting for the dream. It is already a dream come true for a country and a region, so I’m still following my personal dream."
He added: "On behalf of Colombians and Latin Americans we’re very happy because it’s not easy for a Colombian or Latin American to win here. Seeing Egan in yellow really is a source of pride.
"We said that he was going to be one of the greatest and today with his team, he has done it."
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