There was a time when you might have been dismissed as a mere journeywoman if you had not won your first Grand Slam title as a teenager. Martina Hingis was Australian Open champion at 16 in 1997, and it was only seven years ago that 17-year-old Maria Sharapova took Wimbledon by storm.
Today, however, the upper levels of the women's game are dominated by seasoned professionals. Players are fitter and stronger than they have ever been, while restrictions on the number of senior tournaments that juniors can enter inevitably mean that players have a longer route to the top. There are now only six teenagers in the world's top 100, while the youngest player in the top 150 is Britain's Heather Watson, who will celebrate her 19th birthday in May.
Watson, who comes from Guernsey but has been based at Nick Bollettieri's academy in Florida since the age of 12, won the US Open junior title in 2009 and made her debut on the main Women's Tennis Association tour last year. In only her sixth tournament, in Auckland a fortnight ago, she reached her first quarter-final after winning three matches in qualifying and beating Spain's Carla Suarez Navarro, the world No 57.
Having climbed to a career-high No 149 in the world rankings, Watson enjoyed the experience last week of attempting to qualify for a Grand Slam tournament for the first time. It ended in defeat in yesterday's second round of qualifying here at the Australian Open – Anne Keothavong was the last Briton left in the competition going into today's final round – but her gritty performances underlined her undoubted potential.
Although Watson does not have the same weight of shot as her 16-year-old compatriot Laura Robson, she is an outstanding athlete who has matured rapidly as a player. "The big difference now is that she doesn't panic when she gets ahead in a match," Bollettieri said. "She believes in herself. She's also finding the right balance between forcing her opponent into a mistake and going on the attack."
What does Watson herself see as her strengths? "I'm a quick mover around the court," she said. "At the moment my serve is good. I hope it stays that way because I feel it can be a bit up and down at times." And her weaknesses? "I'm not going to tell you," she said with the mischievous laugh that regularly punctuates much of her conversation.
Although she has adapted well to playing senior tennis, she admitted that the transition from juniors had been a big challenge. "Your first rounds are never easy, the rallies last longer and the players have bigger serves," she said. "You have to put more balls in the court. And seniors never give up. You don't get many opportunities and you have to take them. Matches can go quickly."
Watson is no longer a student at Bollettieri's academy, having finished her studies last summer, but will still spend much of her time there, though she will be based at the National Tennis Centre at Roehampton when she is playing tournaments in Europe. The Lawn Tennis Association, which helped to fund her latter years in Florida, now pays for her coach, Billy Wilkinson, to travel full-time.
Flo Pietzsch, the LTA's strength and conditioning coach, visited Watson in Florida and devised a fitness programme for her to follow during the off-season, including two-and-a-half-hour sessions in the gym and four-mile runs on the beach. "That was the hardest part for me because I hate running," she said. "I don't mind doing sprints, but this was four-mile runs on the sand. It was tough. Billy would say to me, 'We're halfway through'. But I would just think, 'Oh no. We've got to do the same thing all over again'."
Watson, who spent only 12 days in Guernsey last year, initially went to Florida on her own but her mother Michelle joined her three years ago. Her father Ian stayed in Guernsey, where he worked for the island's electricity company, though he has now retired and will travel with his daughter to more tournaments this year.
Father and daughter speak on the phone almost every day. "We're very close – I'm a Daddy's girl," Watson said. "He's very parental. He always says: 'I'm doing this so you'll never say later, "Dad, I could have done better if you had pushed me more".' He's definitely the motivator."
Watson's initial target this year was to break into the world's top 100, but after her flying start to the season she is now aiming to reach that target by the time of the US Open at the end of the summer.
What does she think she can achieve in the longer term? "I have my dreams. I want to be No 1 in the world. I want to win at least one Grand Slam, hopefully many. I want to see my name up there on the wall."
Most young players would give a similar answer, so how high does Watson really believe she will reach? "No 1," she said, without a moment's hesitation. "I can do it. I don't know if I will, but I can."Reuse content