It's more a tennis problem than a mental problem. The transition is difficult. It depends how much time you have. Playing on grass can sometimes be a bit of a lottery.
There are some guys you have problems beating because of their style - I always had difficulties with guys like Michael Chang and Andre Agassi because their returns were so good and they played so well in defence.
Tennis is one of the only sports in America where the sport doesn't grow with the size of the person - it just forces you to swallow the whole pill.
Coming from a country that loves tennis, actually, there are a lot of people who play. We definitely face a lot of challenges when it comes to producing tennis players.
No player can become accustomed to New York's climate in August in a few days. The playing conditions, the courts in New York and France are very different.
The conditions change so much at the French Open, you know, you have to be prepared for something you really don't know what it is. You can practice in the morning and it's fine, and the weather is great then you come to play in the afternoon and it is drizzly and the conditions are totally different.
That's why the tactics are so hard against Kyrgios because no one knows what he is going to do.
Against Novak and Rafa, you have balls to hit, but they are so physically really tough. And Roger, he just takes position in the court. He tries to go forward all the time, go for the winners. Then you just don't play tennis against him.
Most of the girls who were better than me went to college or quit tennis. It's interesting to see who stuck around. It's pretty crazy to see who was good in juniors, who tried going pro. A lot of people fall off and it's really that difficult to get to each level.
People think that there is so much money in tennis, but the reality is unless you're ranked in about the top 50 you don't earn much at all. It is hard to support yourself travelling the world, to be away from home most of the year and to pay for a coach to help you become a better player.
Maybe for a guy like Zverev or Federer, you could say it's open a bit. For a guy like me, every match is tough, and I'm going to have to battle it out.
