Emma Raducanu's stunning US Open triumph showed the British teenager can "rule the world" of women's tennis, according to her former coach.
Raducanu has become a global sensation after the 18-year-old stormed through qualifying to win the US Open in just her second Grand Slam appearance.
She defeated Leylah Fernandez in Saturday's final in New York to become the first British woman to win a Grand Slam singles title since Virginia Wade at Wimbledon in 1977.
Raducanu's former coach Mark Petchey knows just how talented and focused she already is.
Petchey believes Raducanu could emulate the sustained success of former men's world number one Andy Murray, who has also worked with the coach.
"From the first day that I met her at the National Tennis Centre, she does have something a little bit special," Petchey told ITV on Monday.
"When I worked with Andy Murray for a year as well and obviously watching Andy from 16, he also had this ability to be able to pick up a tennis ball and in a sport that is played in fractions of seconds that allows you to do very special things, and Emma has that.
"I think everything could be improved; I think her service is still a work in progress. I think her net game is going to get even better as you get a greater understanding of where to be.
"I think her room for improvement is not just incremental gains, I think they are substantial and I honestly think she is going to rule the world."
Her astonishing run at the US Open has lifted Raducanu to a career-high 23rd in the new WTA rankings on Monday, up 127 places from her position before the tournament.
Raducanu is the first qualifier to win a Grand Slam and former British number one Tim Henman expects her victory to provide the springboard for a glittering career.
Henman became Raducanu's unofficial "courtside cheerleader" in his role as a television pundit in New York and she singled him out as an inspiration in her victory speech.
"What's been astonishing is how she's taken it in her stride, at 18 years of age," Henman told the BBC.
"She's handled herself so well. For British tennis, British sport and for world tennis it's really changed the landscape.
"She's the real deal, and she's going to win more of these events in the future. She's going to be a superstar in this sport."
However, Wade, who also won the US Open in 1968 and the Australian Open in 1972, warned that dealing with an increased amount of exposure could be the most difficult change for Raducanu.
Japan's Naomi Osaka won the US Open early in her career and has since struggled with the level of scrutiny of the modern-day athlete.
Osaka, 23, is currently taking a break from tennis, with no date set for her return.
Raducanu, who born in Canada to parents from Romania and China and moved to Britain as a toddler, now has to negotiate the same relentless spotlight that comes with her ground-breaking success.
Asked how she should handle the new level of fame, Wade told the BBC: "That is probably the hardest thing these days, to handle that and so she's got to have very good advice on that."