Kate Middleton tells Emma Raducanu she is 'so proud' after US Open win

After such an incredible performance on the tennis court, it seems only fitting that Emma Raducanu now has royalty rushing to congratulate her.

Kate Middleton told the teenage champion that she was "so proud" of her after the 18-year-old won the US Open on Saturday.

In a post on Instagram, the Duchess of Cambridge, 39, praised the young British champion's "stunning performances" at the prestigious New York-based tournament.

In a gripping final, she beat Canadian player Leylah Fernandez, 19, in front of 24,000 onlookers at Arthur Ashe Stadium at Flushing Meadows.

Captioning a picture of Raducanu beaming while holding up her trophy, the royal mother-of-three wrote: "Huge congratulations @EmmaRaducanu on your stunning performances and historic Grand Slam victory!

"Incredible – we are all so proud of you."

Her post has been 'liked' more than 274,000 times, with over a thousand social media users rushing to praise the "superstar" player in the comments section.

The new British number one, who was born in Canada to a Romanian father and Chinese mother, grew up in Bromley, south London.

Prince William's wife also sent a sweet message to the runner-up, telling her: "@LeylahFernandez well done on your amazing achievements at this year’s #USOpen, it’s been a pleasure to watch."

The duchess is a well-known tennis fan, and has been patron All England Lawn Tennis and Croquet Club since 2016.

Raducanu first came to attention this year as a 'wildcard' at Wimbledon, where she reached the fourth round.

The Queen also posted her congratulations on Twitter, telling her that it is "a remarkable achievement at such a young age, and is testament to your hard work and dedication".

The monarch, 95, added: "I have no doubt your outstanding performance, and that of your opponent Leylah Fernandez, will inspire the next generation of tennis players.

"I send my warmest good wishes to you and your many supporters."

She finished by signing of with "Elizabeth R".

After her evening win, Raducanu changed out of her tennis gear and into a black sleeveless dress and white trainers for a photocall with her trophy.

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