This is from page 170 ff of Anders Haahr Rasmussen's 2010 book "Én bold ad gangen: Wozniacki, US Open 2009". This is my translation. Any errors are mine or the magic elves'.
It's impossible to know if a notebook will turn up some day with Piotr Wozniacki's megalomaniacal imaginings about his 10 year-old daughter's future. I doubt it. It is, on the other hand, well documented that a 10 year-old Caroline Wozniacki, in her first interview with newspapers and TV, made her ambitions known: to become number one in the world and win all four of the Grand Slams.
It would be dangerous to idealise a child's internalised parental ambitions, but it's unclear at times who is pushing whom.
When Caroline Wozniacki won the Pilot Pen tournament in New Haven the week before, I was in the near by beer tent after the trophy presentation and was chatting with her father. He was surrounded by Polish friends and family, the beer was cold and the mood excited, when Caroline showed up and told her father that the car was coming to pick them up shortly, and that she wanted to drive to New York immediately.
"When she was young, I thought, maybe she wants an ice cream or something when she said 'daddy daddy, get up, come and run,'" relates Piotr Wozniacki, " but now I see that it's really because she's more ambitious than I am. She's a different person than I am."
"It can cause problems understanding each other, because her ambitions are different from mine. I was never as ambitious as she is. My ambitions were never to make the national team and be amazing like Laudrup. He would understand, probably, but I was never at that level, so I don't understand these things. Even now my ambitions are different from hers, I'm here and she's there," he says, holding his right hand much higher up than his left.
"Sometimes I look in the mirror and think 'Hell, I need to be more active', I need to be more professional. It isn't enough if I tell her to hit a few backhands and hit a few forehands, because she'll just look up and say, 'what kind of crap is that, that's not good enough, either we work, or we don't.'"
I asked Piotr Wozniacki, who's never played tennis for more than the exercise, how he keeps up.
"I'll explain it very simply: you buy a ticket for the front row in the circus. You see an elephant doing things a normal elephant doesn't do. So you think 'damn, how many hours has it taken to get that elephant to be so good at those things?' We humans have the advantage that we're more intelligent than elephants. It's taken thousands of hours of practise for me to do the things I can do. It's the same when you go to primary school, then gymnasium (high school) then university. How many years has it taken? Quite a few.
"I've been on court from when Caroline was seven to today, and I hook her up constantly with different coaches and people, and I talk to them, and I get more and more knowledgeable and better as a tennis coach. I've used all my energy on that education, in that circus, so it's becoming easier for me to understand those things, and it's getting better for Caroline, because we can communicate about the same things.
"Getting back to the elephant, I'm the elephant, and the trainer was Caroline. She was on the court playing, so she knew and understood those things better, and by the communication we had every ten minutes, every day, every month, every year, that elephant started to figure those things out."
I still don't know who's which elephant, and I still don't understand what made him sacrifice all his time for his daughter's hobby, but it's made a world of difference for Caroline Wozniacki.