Emma Raducanu made tennis history Saturday after beating Canadian rising star Leylah Fernandez to win the US Open. Sure enough, Queen Elizabeth II, the Duke and Duchess of Cambridge, and the whole British Royal Family were delighted as they watched the 18-year-old bring pride to the nation.

The teenage sensation beat Fernandez in straight sets–6-4, 6-3–in what turned out to be one of the most memorable Grand Slam final in recent history. The all-teen finale didn't disappoint, with Raducanu showing her power and serve while Fernandez did her best to stay close all match long.

In the end, though, Raducanu proved to be too much and too strong for her US Open foe, getting three service aces and winning 72 percent of her first serve points. More amazingly, she didn't drop a set throughout the competition–a feat last achieved in the Majors by Serena Williams in 2014.

After the win, Queen Elizabeth II sent an open letter to Raducanu for her incredible US Open showing, via Evening Standard:

“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,” the Queen wrote.

“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.”

Aside from the Queen, the Duke and Duchess of Cambridge–Prince William and  Kate Middleton–also sent their congratulatory message to Emma Raducanu on Twitter.

Raducanu's US Open win is truly historic. Not only did she end Britain's 44-year wait for a Women's Grand Slam singles championship, but she also became the first qualifier in the Open era to win a Slam. Heading to the competition, she was ranked no. 150 and had to go through three qualifiers to make it to the official tournament.

Furthermore, she also became the youngest women's major champion since Maria Sharapova in 2004 and the youngest Brit to win a Slam.