Love is so much more than a tennis term for Katie Boulter and Alex de Minaur, who just got engaged!

The British bride-to-be and Australian groom-to-be announced the news via Instagram on Monday, Dec. 23. “We’ve been keeping a small secret… 🤭,” Boulter captioned a joint post in which she smiles next to her fiancé in a selfie.

In the sweet snap, Boulter’s left hand rests on de Minaur’s chest, prominently displaying her new rock — an emerald cut diamond on a simple, thin band.

PEOPLE has reached out to the couple for comment. 

Congratulations filled the comments section of the post.

“Thrilled for you both 🥹 Congrats!” the official Australian Open account wrote.

Many fellow professional tennis players, such as Thanasi Kokkinakis, Anna Kalinskaya, Paula Badosa, Victoria Azarenka, Zeynep Sönmez, Rinky Hijikata and Emma Raducanu, expressed their excitement over the engagement in the comments.

Boulter, 28, and de Minaur, 25, met on the tennis circuit, both made their Olympics debut this year, and have been dating for more than four years. They could face off in direct competition at the United Cup in Australia early next year as Great Britain and Australia have been drawn in the same group for the tournament. 

The 2025 United Cup will be held from Dec. 27 to Jan. 5 at the RAC Arena in Perth and the Sydney Olympic Park Tennis Centre. With two singles matches and a mixed doubles tie in every fixture, the newly engaged couple could play against each other if selected for the doubles.

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Before announcing her engagement, Boulter — who is ranked No. 24 in the world for women’s singles and is the British No. 1 — told Sky Sports News how she was feeling about potentially facing off against her longtime love.

“I wouldn’t say I am thrilled at the idea of playing him all over again,” she said, as De Minaur is the world No. 9. 

“Obviously, he is a top-10 player and he knows how to play tennis, so there’s one side of it” she continued before adding, “Then there’s a personal side of it as well, which is difficult but also great for bragging rights.”

Playing together, Boulter and de Minaur reached the second round of the mixed doubles at Wimbledon last year.

Based on Boulter and De Minaur’s respective Instagram Stories, the two are spending Christmas Eve at Bondi Beach in Sydney, Australia, with British tennis player Jodie Burrage.