Fuglsang, riding for Astana, launched an attack with just one kilometre to go in the 147.5km route from Le Parc des Oiseaux to La Motte-Servolex.

The Dane was matched for pace by Australia's Richie Porte with the Lotto-Soudal racer sprinting on the right side of the road and seemingly set to claim the win.

Fuglsang managed to produce enough speed to pass him in the dying stages and cross the line first in a time of 3 hours, 41min and 48sec with the chasing pack recording the same time. 

Porte took second with Great Britain's Chris Froome of Team Sky trailing in third.

Second place for Porte, who won stage four, was enough to see him surpass Belgium's Thomas De Gendt for the overall race lead.

The Australian has an overall time of 20:52:34 with two stages to go.

“It’s nice to have the jersey, but I know the next two days are going to be super hard,” Porte said.

“I feel up for it.

"I think we have the team here to try to finish it off on Sunday."

Three-time winner Froome moved into second in the general classification, 39sec behind Porte while Fuglsang occupies third 1:15 back.

Action at the International Cycling Union WorldTour event is due to continue in France tomorrow with stage seven, the penultimate day of racing.

Competitors will race a 168km route from Aoste to Alpe d'Huez.