Astana rider Fuglsang was part of a large breakaway group and launched a solo attack four kilometres from home.

He stormed clear to win by 22 seconds, with Team Ineos rider Tao Geoghegan Hart of Britain taking second place.

Astana teammate Luis León Sánchez of Spain finished third, 40 seconds behind, as race leader Roglič crossed almost six minutes later.

Several attacks were threatened as the 144km stage set off from Pravia, before a large group eventually broke free.

Roglič was part of the lead group, which diminished to just ten riders as the climbs took their toll.

Sánchez attacked the front with Fuglsang with 9km to go as Britain's Deceuninck-Quick-Step rider James Knox, Italian Gianluca Brambilla of Trek-Segafredo and Geoghegan Hart kept close quarters.

Fuglsang made a first move 7km from home, with Brambilla following, while Colombian general classification hope Nairo Quintana of Movistar was dropped by the main group.

A second attack from Fuglsang proved pivotal as he surged clear for the stage victory in four hours 01min 22sec.

Geoghegan Hart crossed in 4:01.44 for second place as Sánchez completed the top three in misty conditions, clocking 4:02.04.

Colombian Miguel Ángel López of Astana launched a separate attack, with Slovenian duo Tadej Pogačar, from UAE Team Emirates, and Team Jumbo-Visma's Roglič in hot pursuit.

The trio crossed five minutes and 58 seconds behind stage winner Fuglsang, but close enough behind for Roglič to retain the red jersey heading into tomorrow's rest day.

Roglič leads the general classification in 62:17.52, extending his lead over Spaniard Alejandro Valverde to two minutes 48 seconds.

Pogačar is in third place.

The race continues on Wednesday (September 11) with the 17th stage, a 219.4km route from Aranda De Duero to Guadalajara.