The serve, I think, is the most difficult, you know, in terms of coordination, because you got the two arms going, and you got to toss it up at the right time so.

I'm playing great tennis. I'm enjoying the tour, having fun with the fans off the court. I'm loving it now.

I had set a goal with my team to try and get back to the top of the rankings, but I never thought with the depth in the game this year that I would have been able to get it back so quickly.

I'm not angry. As an athlete ... you should be open to criticism, and you're allowed to be criticized, because not everybody has the same opinion, not everybody likes the same players. The rankings are quite volatile: Today you're 'great,' tomorrow you're 'not,' but then you're 'great' again. It makes for great stories. Now, I always look at the long term and by doing that, obviously, I can stay calm through the storm.

Tennis can be a very frustrating sport. There is no way around the hard work. Embrace it. You have to put in the hours because there is always something you can improve. [Y]ou have to put in a lot of sacrifice and effort for sometimes little reward but you have to know that, if you put in the right effort, the reward will come.

With all the injury problems we have in men's tennis at the moment, I'm happy to still be standing.

I haven't had a cramp since '99. That was my only time, in Davis Cup, when I was panicky. I was young. I'm very proud of that. Never pulled out. Never had cramps. Never lost very much because of fitness, especially later on in my career where I knew I've put in the hard work. I've done that. I've been very fortunate and clever as well to understand how I need to work, when I need to work. So I'm very happy to have stayed injury free for so long. I hope I can still maintain a few good years on the tour. I really hope so.