MELBOURNE // Novak Djokovic's defence of his Australian Open title ended prematurely today when the Serb was forced to retire from his quarter-final against Andy Roddick after the third game of the fourth set. The American player Roddick had been leading 6-7, 6-4, 6-2, 2-1 when a visibly distressed Djokovic said he could no longer continue. The 21-year-old had called a medical time out after the third game of the third set, when he had held serve to take a 2-1 lead, but looked exhausted when play resumed and lost the next five games.
Roddick held four break points in the first game of the fourth set and while Djokovic battled back to hold serve it may have sapped any semblance of energy he had left, as the seventh seed won the next game then broke him to love. The third-seeded Djokovic then walked off court, consulted the doctor and told chair umpire Carlos Ramos of Portugal "no more", before he went to congratulate Roddick, who has now advanced to his fourth Melbourne Park semi-final. The last men's grand slam champion to quit while defending his title was Pat Rafter at the 1999 US Open. Rafter retired in the fifth set of his first round match against Cedric Pioline.