Novak Djokovic loses in Round 1, cries on court before shock exit

Novak Djokovic's early exit from the US Open is a major shock to tennis fans after a stellar quest for the 25th record-breaking Grand Slam fell victim in the very first round.

Fourth seed Djokovic was defeated by Argentina's Mariano Navone in a five-set thriller at the Arthur Ashe Stadium as the Serbian tried to better his record of 25 Slams.

Despite a superb fightback after losing the first set, Djokovic was unable to cope with his own physical difficulties as he eventually lost 6-7, 7-5, 6-4, 2-6, 1-6.