I'm thankful to be able to team up with a company like USANA that cares about my well-being and I know we can do great things together.
I never give up. Doesn't matter what the score is.
My parents paid me small amounts for cleaning my room or cleaning the dishes and stuff, but I never really had a real job before I started on my professional tennis career.
I feel like everything is possible.
The only one I feel pressure from is myself to go and give my all for every match and, obviously, I'm a competitor.
I just go out there and fight for every point, and then we see how far I can go.
I do my best, and that's all I can do.
You feel better about yourself when you do something with yourself. You also feel more confident.
I have proven people wrong so many times. I was told when I was younger there is no chance I will make the top 100, top 50, top 30. Every time I have proven them wrong. It's kind of nice.
To be the world No. 1 has always been a dream for me.
You can't dwell in your past but move forward, look forward. That's it.
I think I'm a really tough player.
I'm the type of player I am.
My dad has always been my coach. And I've spent so much time with him. So he's one of my best friends. And I can talk to him about everything.
I believe the best in people. I believe if you need a bathroom break you go to the bathroom. If you need treatment, you get treatment. I don't think any rules should be changed.
I start laughing every time because the media talks to me like I'm finishing my career and I only have one year left and time is running out.
I used to always be the young one playing without pressure, but I am just happy to be where I am and enjoying my time.
I like Twitter a lot. It is a great way to get the fans knowing another side of you.
I'm just taking one match at a time.
There are a lot of things to my game I can still improve, but everyone can.
I don't know, I always get the question 'how do you feel after the game today?' and, of course, if you're winning you feel great and if you lose you don't feel good. I think that's a pretty obvious question.
Young players are starting to come up as well and they will see me as one of the older, experienced ones.
There's just nothing like playing on Arthur Ashe Stadium. It's truly amazing.
I try to be myself and, of course, be a good role model. I don't really find it hard, but you think about what you do and that other people look up to you.
The fact is I still have quite a few good years in front of me. I still improve.
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