The true roots of her win, however, lie in her training at the prestigious Nick Bollettieri school of tennis in the United States, where the Guernsey-born player followed in the footsteps of greats including Maria Sharapova and Andre Agassi.
Her parents, Manchester-born Ian and Michelle, who is from Papua New Guinea, allowed her to follow her dream, giving up their jobs and moving with her to the United States.
Since then she has not looked back, becoming the British under 14 champion and later, the first Briton to win the US Open girls’ junior singles title.
However, it was Wednesday, on Wimbledon’s Court 2 that she rose to national prominence with her straight sets win over Jamie Hampton, an American player.
But two people who were not present to witness her straight set win over American Jamie Lee Hampton were her parents, who decided to “leave her to get on with it” despite being the very reason she got into the sport.
Far from being pushy and competitive, Mr and Mrs Watson have kept their daughter’s feet firmly rooted to the ground and refuse to let her success dominate their lives.
Their approach has clearly worked. Watson has described her father, a former managing director of Guernsey Electricity, as her idol. “He’s just always so calm, and he says no matter how I do, he’ll be proud of me,” she has said.
It was watching her parents play at their club in Guernsey as a toddler that first piqued her interest in tennis.
At the age of nine, she asked them for £10 and used it to enter a a softball tennis competition at a local funfair.
“Five days later I walked into the house with a trophy,” she has said. “My parents asked me where I had got it. I told them that I had entered a softball tennis event and won. They were understandably surprised because they had no idea what I had done.”
Watson has since risen up the rankings to become Britain’s No.3 and will now experience the pressures faced by Andy Murray as the nation holds its breath.
Her natural exuberance has already won her an army of loyal followers and she said she felt an “explosion of happiness” at the end of her match, which was watched by her half-brother Adam, his wife and daughter.
“I love it when the crowd bring a lot of energy and they clap. It gets me quite pumped and really motivated to win,” she said, beaming from ear to ear.
“I’m just so pleased that it’s finally clicking for me.”
Asked if she had adopted any new superstitions, she admitted eating smoked salmon and eggs for breakfast every morning, with toast on the side, and running to pass the ball boy her towel each time she changed ends on court.
She was reluctant to be drawn into the ongoing row over the decision to award female players at Wimbledon the same prize money as the men but admitted: “I think it’s tough for the guys, especially at Wimbledon because it’s five sets.
“At all the other tournaments it should be the same. We play the same amount of sets and have to work just as hard.”
Her smile returned though, as she laughed off suggestions that she may have Scottish blood.
“I knew I had a Scottish name,” she said. “But my dad is from Manchester and my mum is from Papua New Guinea, so no.”
Jose Lambert, one of Watson’s first coaches at IMG Academy in Florida, said the young star had worked on her fitness levels in the run-up to Wimbledon.
He said: “When she came back for the winter, they did a lot of fitness and they would come out and do a couple of hours on the court but the main thing was fitness and a lot of gym work.
“I’m just so happy and so proud of her. I’ve been working with her on and off for eight or nine years before she went with Mauricio Hadad for her professional coaching.
“The Heather I know is just awesome - she’s super competitive, super athletic and very fiery. She’s always been her own person and she has a great sense of humour.”
He said her parents Ian and Michelle had been supportive of her career and backed her to go further in the Championships.