Harriet Dart could overtake Emma Raducanu as British number one after a stunning victory against Daria Kasatkina at the US Open.Dart earned the biggest win of her career with an impressive 7-6, 1-6, 6-3 result against Kasatkina, who has been in brilliant form this season.It is the first time the British star has triumphed in the main draw at the US Open, and her first victory against a top-10 player.The result will give Dart, the world number 88, valuable ranking points. It would also put her within touching distance of Emma Raducanu, if the reigning US Open champion loses the opening match of her title defence.If Raducanu is defeated by Alizé Cornet this evening, Dart would be 11 ranking points behind and one win away from becoming British number one.

“To be honest that’s not something I think about," Dart said.

"It’s more about just day in and out putting my best out there and trying to get my ranking up slowly but surely.

“But if that happens, great. It would be an amazing thing to be able to do, but for me it’s just about day in and out and focusing on what I can control."

The 26-year-old Dart is enjoying one of the best seasons of her career, breaking into the world top 100. She was particularly impressive at Indian Wells, beating Elina Svitolina on her way to the round of 16.

Emma Raducanu and Harriet Dart

The furthest Dart has gone at a Grand Slam is the third round, doing so at Wimbledon in 2019.

In contrast, Raducanu made history at Flushing Meadows last year after becoming the first ever qualifier, male or female, to win a Grand Slam title. She was also the first British woman to triumph at a Grand Slam since 1977.

The 19-year-old has struggled to find her form since, battling with fitness and injury issues, and she will plummet down the rankings if she fails to defend her title.

Raducanu has admitted she is not putting pressure on herself ahead of this year’s US Open, and is willing to rebuild if needs must.

British tennis player Emma Raducanu
NEW YORK, NEW YORK - AUGUST 28: Emma Raducanu of Great Britain smiles in a practice session during previews for the 2022 US Open tennis at USTA Billie Jean King National Tennis Center on August 28, 2022 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Julian Finney/Getty Images)

“If I lose 2,000 points, so be it, I’ll start again from the bottom,” she said earlier this month. “I know I can do something that no one else has done.

“I qualified and won the US Open, so I can start from the beginning, I can start from zero and I’m not afraid of that.”