World number one tennis player Novak Djokovic, in an exclusive interview to NDTV, spoke about his rivalry with Roger Federer and Rafael Nadal. When asked about who he considers his bigger rival Federer or Nadal, the Serbian said it's hard to pick one of them and both have always been tough to play against. The Serbian star said both Federer and Nadal have different style of playing and he always has to make adjustments to his game while playing against them. Djokovic also added that they both pushed him to be a better player.