Novak Djokovic born 22 May 1987) is a Serbian professional tennis player who is ranked the World No. 1 by the Association of Tennis Professionals (ATP) since 4 July 2011. He has won three Grand Slam singles titles, the 2008 and 2011 Australian Open championships and the 2011 Wimbledon Championships, becoming the first player representing Serbia to win a Grand Slam singles title and the youngest player in the open era to have reached the semi-finals of all four Grand Slam events, separately and consecutively.Amongst other major titles, he is also the winner of the 2010 Davis Cup.