Kate and 18-year-old tennis star Raducanu teamed up at the National Tennis Centre this morning. The Duchess, whose love for tennis is very well known, sported athletic attire and hit the court alongside Raducanu after congratulating the teenager on her historic victory at the US Open final.

       During her day out at the tennis centre, Kate also met fellow British US Open champions, Gordon Reid and Alfie Hewett, who won the men's wheelchair doubles - and men's doubles champion Joe Salisbury.

       The Duchess gushed over their achievements.

       Kate candidly told them they were "amazing".

       She added: "Guys, honestly, congratulations!"

       Calling them "seriously impressive", she added: "It's so nice for all of you to be back here in your home country so we can celebrate you in the home of British tennis."

       The homecoming event was hosted by the LTA Youth, a programme which helps people aged between four to 18 to get involved in tennis.

       After congratulating Raducanu and her fellow champions, Kate met children involved with LTA to hear their aspirations.

       She also heard more about what LTA is doing to improve participation.

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       Kensington Palace said: "Her Royal Highness is passionate about supporting grassroots tennis and encouraging young people from all backgrounds to become involved in the sport."

       Kate, who is the patron of All England Lawn Tennis and Croquet Club (AELTC), has shown her support for Raducanu since this summer.

       As Wimbledon was taking place, the Duchess tweeted from the official social media account she shares with Prince William: "Unbiased prediction to win it: @andy_murray and @EmmaRaducanu #Wimbledon."

       The teenager was forced to drop out of the tournament due to medical reasons but showed appreciation for the royal support received.

       Raducanu responded to Kate and William's tweet saying: "Ah not quite this time but thank you so much for the encouragement!"

       Her reply caught the attention of the royals' official Twitter account, who put a like on Raducanu's message.

       Kate closely followed Raducanu's performances at the US Open too, as she tweeted after the 18-year-old gained a place in the final: "What an incredible achievement at this year's #USOpen @EmmaRaducanu!

       "We will all be rooting for you tomorrow. Wishing you the best of luck!"

       The Duchess of Cambridge signed off her message with her initial 'C', to clearly state she was the person behind the tweet.

       Similarly, after her victory, Kate took to Twitter again and, in another post ending with a 'C', she wrote: Huge congratulations Emma Raducanu on your stunning performances and historic Grand Slam victory! Incredible – we are all so proud of you.

       "Leylah Fernandez well done on your amazing achievements at this year’s #USOpen, it’s been a pleasure to watch."

       Raducanu didn't only impress the Cambridges - as she received a public message of congratulations also from the Queen.

       She wrote: "I send my congratulations to you on your success in winning the United States Open Tennis Championships.

       "It is a remarkable achievement at such a young age, and is testament to your hard work and dedication.

       "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."