"I don't think I should even be going into this conversation," she says, laughing. "Uhm, I think he's done a very good job ... Hah! Yeah ... whatever he's doing is obviously working ... tennis‑wise!"
There is a lot to like about Robson. Not only has her tennis matured to the point where the expectations heaped on her are now reasonable rather than idiotically out-sized, but she has somehow hung on to her all-round niceness in a sport that does not always encourage that quality.
Robson, currently ranked 53rd in the world, leads, we discover, a reassuringly normal life. She passed her driving test a year ago, but does not own a car and rarely drives because she prefers to travel by Tube. She flies down the back of the plane, because, well, it's all she can afford – and, anyway, she doesn't suffer from jet-lag because she can sleep anywhere, any time. She has no plans to leave home, because her mother, Kathy, is such a good cook. She finds China boring, and kills time there making Gangnam videos on her iPad (the latest of which went viral on YouTube). And, no, Serena is not the queen bee of tennis.
"I've always found her very pleasant," she says. "The locker room doesn't really revolve around any one player – people just shower and leave. But I've had a good locker, the same one at the US Open the last two years.
"I've got [Maria] Sharapova on one side, Serena on the other, then it's all the past champions in various different places. I've got a [Martina] Hingis locker near me, but I never really want to take the past champion's locker. This year they had a qualifier using Hingis's locker and I thought, maybe best to leave that to one of the senior players."
Hingis would like that. The Swiss invited Robson to join her to train when Laura was 11, and the thrill for the London prodigy has stayed with her ever since.
For someone with realistic ambitions of breaking into the top flight after a wonderful 2012 – in which she beat the former world No 1 Kim Clijsters at Flushing Meadows in the Belgian's farewell appearance, gave Sharapova a fright at the Olympics and then won a silver medal with Andy Murray in the mixed doubles – Robson is well grounded. She's not even sure how much she is worth and, no, she is not remotely near being a millionaire. "I wish!" she squeals.
Did she think she'd changed much since sending the media into overdrive by winning Junior Wimbledon when she was 14? "I think I was nicer then," she says. It's hard to believe – especially when she says the last time she was "super angry" was, "when I was 13 and I was playing my coach in a mini-tennis game. I was playing with my right hand, he was playing with his left, and I lost a best-of-five match, each set up to 10, and I broke one of my rackets." Disgraceful.
But Robson can see humour where others see only discord and controversy. She rather enjoyed, for instance, Novak Djokovic's spectacular racket-bashing in Shanghai recently. What has become the most irritating trend in women's tennis, grunting, bothers her not a jot.
In the moment of her greatest triumph, against Clijsters, the enormity of the occasion barely disturbed her sense of wonder. "That was the first time I'd played on Arthur Ashe so you have to enjoy yourself when you're on there. It was after the first set and they played a Taylor Swift song, and I was singing on along to it. I looked up at Abi [Tordoff, her long-time agent] and she was giggling. Then I thought, no, I shouldn't be singing this song. So, after that, I tried to focus a little bit more."
How distant is such innocence from the cynicism perceived to be at the heart of professional sport? Yet Robson somehow carries her personality on to the court, hitting as freely as she glides through life, without a care for unknown consequences, yet not disrespectful of the demands and pressures of her high-powered existence.
She only recently was acquainted with the financial side of her life, when her father, Andrew, took her to see the local bank manager. She was surprised to learn in those talks that, "almost 30% of footballers end up going bankrupt, so my dad is being very, very cautious – not that I would ever go crazy. You just have to be aware that it is such a short career and you have to do as much as you can to save."
To that end, she shops within the confines of the allowance he gives her – and she doesn't waste money on travel, either. "I'm paying for my own flights, so it's definitely economy. I've never really suffered from jet lag. I have the gift of being able to sleep anywhere; even in cars on the way to the airport, I'm fast asleep. I like the window seat, and I just don't get up for eight hours. On the way to China, I slept for a solid 12 hours." Does her new coach, the no-nonsense Croatian Zeljko Krajan mind the cost-cutting? "I think so, but he has to deal with it. Business class is too expensive for my ranking."
What do other passengers think, sitting alongside a sports celebrity down the back of the bus? "A few times people say hello; it's a bit awkward when they ask for a photo as well."
It's all still a grand adventure, and Robson doesn't see it changing soon. All she wants for Christmas – her first at home since 12 months before she won Junior Wimbledon – is another puppy. "But maybe three dogs is too much ..."
guardian.co.uk © Guardian News and Media Limited 2010
image: © marianne bevis