By Simon Cambers
NEW YORK (Reuters) - When Laura Robson won the Wimbledon junior title as a 14-year-old in 2008, former players were falling over themselves to tip her for the top.
Four years later and the British left-hander with the big forehand and a quick wit is starting to deliver.
Already the youngest player in the women's top 100, the 18-year-old followed her shock win over three-times champion Kim Clijsters at the U.S. Open this week by stunning former French Open champion Li Na of China in the third round on Friday.
It was a performance full of power and maturity for such a young player, making her the first British woman to reach the fourth round at Flushing Meadows since 1998.
Her world ranking of 89 is set to rise to at least 75 and if she beats defending champion Samantha Stosur in the fourth round on Sunday, she would climb to the verge of the world's top 50.
"I think the level has always been there," a delighted but refreshingly level-headed Robson said. "In the last few matches I think it's noticeable that instead of just trying to hit a winner off a tough shot like I have done in the past, I'm just trying to make a percentage shot back.
"That makes all the difference really."
The arrival of a new coach in Croatian Zeljko Krajan just three weeks ago also seems to have done the trick.
"In the last few weeks I have gained a bit of confidence and the work that I have done with him has been very specific in terms of tactical stuff," she said.
In her steady rise up the rankings, Robson has had her fair share of injuries including a stress fracture in her shin and a groin problem.
Now injury-free, Robson has been working with Andy Murray's fitness trainer, Jez Green, and in her three wins in New York, her movement around the court has been a revelation.
"(Being fully fit) has been massive," she said. "It just makes so much of a difference mentally. I just feel like I'm healthy. This is my third match and I'm feeling fine, I'm feeling fit."
Robson won a silver medal at the London Olympics in mixed doubles with Andy Murray and said that experience, as well as pushing Maria Sharapova hard in the singles, helped boost her confidence.
"I have always thought that I can play with the top girls," she said. "Whenever I've practiced with Caroline (Wozniacki) or Maria, I've always felt that the level was there.
"It was just taking that onto the match court and keeping the level up for the whole match. That's what I have worked on. That's been the biggest difference."
Born in Australia, Robson's parents moved the family to Singapore when she was 18 months old and then to Britain as a six-year-old.
With Virginia Wade the last Briton, male or female, to win a grand slam singles title at Wimbledon in 1977, Robson has to deal with plenty of expectation on her shoulders.
Manchester United's Wayne Rooney tweeted his congratulations after her victory over Li and she spotted British comedian James Corden in the stands during that match.
"I was trying not to wave," she laughed. "But Wayne got my name wrong. He said Robinson."
The 18-year-old's sense of humor already shines through in news conferences, and she was quick to put down an Australian who suggested she might want to change her nationality back to the country of her birth.
"I get asked that every time by an Australian journalist," she said. "I don't think my answer has ever changed. Still a no."
(Editing by Frank Pingue)
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