Britain’s newest sporting star, Emma Raducanu, has put her stunning success at the US Open down to her “very hard-to-please parents”, who she said had given her the mental strength to succeed. Such is the 18-year-old’s burgeoning popularity in the United States that she was invited on to two of America’s flagship programmes – ABC’s Good Morning America and the NBC Today Show, each with more than 3 million viewers – to talk about winning her first tennis grand slam tournament. Raducanu laughed as she told ABC’s presenters that even her father, Ian, and mother, Renee, had been impressed when she called them after her victory on Saturday night. “It was really nice to talk to them after I won,” she said. “They were just so happy and proud of me and my toughest critics, and very, very hard to please. But, yeah, I got them with this one. They couldn’t resist.” Due to strict Covid-19 rules, Raducanu’s parents could not be in New York to see her extraordinary run in the tournament end with her first grand slam title and a $2.5m (£1.8m) cheque. But she stressed that they played a crucial role in helping her develop the resilience to deal with the pressure she faced in New York. “I think that from a young age I’ve always sort of been brought up to have mental strength,” she told the presenter George Stephanopoulos. “My parents played a huge part in my upbringing and they were pretty tough on me when I was young, but it kind of shaped the way I am. “And I think now it’s helping on the biggest stages in the world, and Arthur Ashe stadium, when you really need it, and it was basically at full capacity – so it was very, very cool.” Appearing on NBC an hour later, Raducanu admitted she was still getting to grips with her astonishing run in New York, where she became the first qualifier to go on to win the title. “Three weeks ago I did not think I would last the whole trip. I thought that I would be home in a week, after qualifying,” she said. “Now three weeks later the time has flown and I was holding the trophy at the end. It was the best time of my life.” In a post on Instagram, she revealed she had been sightseeing in New York. Later on Monday she will also attend the Met Gala, the Oscars of the fashion world. Raducanu, whose victory has catapulted her from 150th to 23rd in the world rankings, also had a message for other young athletes who wanted to succeed. “It’s inner belief and just taking care of each day as best as possible, because 10 matches ago, when I was playing my first-round qualifiers, I did not think I’d be in the US Open final or winning it.” One of her coaches, Andrew Richardson, agreed that Raducanu’s biggest asset was her mental strength. “Her ability to deal with adversity and compete is where it all starts,” she said. “I’ve known her from a young age, and she’s always had that. I’m not sure it can be coached. I think a lot of it is parenting, and her parents should take a lot of credit for the person Emma is. The mental strength she has is truly special.” Raducanu smiled as she told Good Morning America she had celebrated her victory with a quiet night with her coaching team rather than partying. “Honestly, I haven’t checked my messages yet,” she said. “I’ve just been trying to enjoy the moment. And with my team on the night of the final, we just had a really nice night. We all spent the night just reflecting and it was a really cool moment because it’s been such a long trip for us and everything has gone so fast. We just got to reflect and share a few stories and it was a really nice night to have with everyone.” Raducanu also thanked the Queen for sending her a message of congratulations following her victory on Saturday, saying: “It is absolutely insane to think … it’s incredible. I was so honoured and grateful to receive a note from Her Majesty. I mean, it meant everything to me, and I’ll probably frame that letter and keep it in my room or something.”