Reigning Tour de France champion Chris Froome kept alive his hopes of completing a stunning Grand Tour double by closing to within one minute and 21 seconds of Vuelta a Espana leader Nairo Quintana on Friday, courtesy of a magnificent time trial performance.

Froome - the time-trial bronze medallist at last month's Olympic Games - was the emphatic winner of stage 19, a 37 kilometre dash from Xabia to Calp.

The Team Sky rider finished 44 seconds clear of his nearest rival, Movistar's Jonathan Castroviejo, while Quintana was two minutes and 16 seconds off the pace - leaving the Colombian more vulnerable than he may have anticipated ahead of Saturday's penultimate stage.

Froome will have known the time trial provided his best chance to make inroads into Quintana's previously healthy lead in the battle for the red jersey.

And the Briton - seeking to become only the third man to win the Tour de France and Vuelta in the same year - since duly set off at a blistering pace, completing the first section of the course almost half a second quicker than Castroviejo.

Quintana (Movistar) was unable to match Froome's exceptional speed and had to settle for 10th position.

Attention will now turn to stage 20, a mountainous route from Benidorm and Alto de Aitana that provides Froome with his final chance to get in front ahead of the chiefly ceremonial final journey to Madrid.

Alberto Contador (Tinkoff) is more than two minutes adrift of Froome in third place.