My nutritionist has done a great job in changing my diet after we established I am allergic to things like gluten - I can't eat pizza, pasta and bread. I have lost some weight, but my movement is sharper and I feel great.
Tennis players we're always playing in center courts that feel like arenas. And when we get on the court and the crowd cheers your name or salutes you - it's like you're a gladiator in the arena. And everyone is cheering - and you're fighting, you're screaming, during your strokes - it feels like you're an animal, fighting for your life.
I have been through two wars in my 24 years, and I know what it's like to be without anything, to see the bombs flying above your head.
It gives me goose bumps and little butterflies in the stomach when I start thinking about the 'golden slam.'
I'm trying not to pay too much attention to the rankings because calculations can distract you.
I had to listen to the classical music because it calms me down, calms my nerves down.
It's interesting that I had such a close relationship with my grandfather. Because your parents always judge you: they say, 'You shouldn't do this, you shouldn't do that.' But with your grandparents you have a feeling that you can say anything or you can do anything, and they will support you. That's why you have this kind of connection.
Even though now I'm pretty popular in my country and tennis is the No. 1 sport, and I'm very flattered that the people recognise me and come up and give me compliments, I'm more a person who likes to have privacy and peace.
Imagine a part of the U.S.A., from which the U.S.A. started - where is the cradle of your history? This is Kosovo for Serbia.
My mother is a special story. She went through so much to bring us up, four men at home, especially when our country was going through really difficult times.
Building a solid foundation in the early years of a child's life will not only help him or her reach their reach their full potential but will also result in better societies as a whole.
I'm a happy man, because I am successful in what I do, of course; but what makes me most happy is I have people around me that I love and who love me back. This, for me, is the most important thing. Nobody likes to be alone.
Joking around is part of my personality, just who I am.
I don't think there has been enough communication between the players and the tournaments. In one sense it's just as much the players' fault. Players talk between each other and in the locker room about things that can be improved and then when the time comes to talk and really do something about it they stop.
I love football and it's the sport I would really like to play. I've said on national television here that I would really love to play for one of our football clubs when I finished my tennis career.
In my case, I can sincerely say that nothing is impossible... When I was saying I want to be No. 1 of the world, and I was seven or eight years old, most of the people were laughing at me because it seems like I have one percent of chances to do that, and I've done it.
And when I was saying I want to become number one of the world and I was 7, 8 years old, most of the people were laughing to me. Because you know, it seemed like I have one percent chances to do that. And I've done it.
The tradition in Serbia has always been team sports - football, basketball, handball, volleyball and water polo, individual sports are not supported.
My father had never watched tennis, never liked tennis too much. He said, 'OK, we buy a racket, we watch together,' because we didn't know anything. It was a process of learning together that made it more interesting.
The history of our country is cruel. We have to face those issues or, should I say, we had to. Not anymore I hope, because we are going in the right direction, and we are ready to forgive, ready to move on.