New York: Rafa Nadal ended a sub-par grand slam season on a heartbreaking note when he fell 3-6 4-6 6-4 6-3 6-4 at the US Open to an inspired Fabio Fognini after winning the first two sets at Flushing Meadows on Friday.

Clay court specialist Fognini, who was 0-7 on hard courts coming into the US Open, played magnificently from the third set on, picking Nadal apart with groundstroke angles and deft play at the net, where the Italian won 39 of 54 advances.

The final set produced spectatcular rallies and winners that had the Arthur Ashe Stadium crowd on their feet well after 1:00am as the combatants traded seven service breaks in a row from the third game of the fifth set before Fognini held to end the three hour 46-minute tilt.

The defeat ended eighth-seeded Nadal's streak of 10 years in a row with at least one grand slam singles title after the Spaniard lost in the quarters at the Australian and French Opens, while going down in the second round at Wimbledon.

It was Nadal's first grand slam defeat after winning the first two sets of a match. The only previous such defeat in his career came in the 2005 Miami finals to Roger Federer.

Fognini advanced to a fourth-round match against Spain's Feliciano Lopez, a 6-2 7-6 6-3 upset winner against 10th seeded Milos Raonic of Canada.