The stunning royal wore a gorgeous crisp white blazer from Zara with her hair in her signature long waves and could be seen cheering on the English team from the stands, along with many other fans.
Keep reading to see some of Kate's best moments at the nail-biting event...
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Kate's arrival
The Princess wore a stunning white blazer and dark trousers for her arrival at the match between England and Fiji, which was held at the Stade Velodrome in Marseille.
Kate, who is a huge fan of rugby, has been attending more events without her husband and seeming ever more confident in her royal role since becoming Princess of Wales.
The mum-of-three appeared to be sharing her insights into the game with her seatmates as England played Fiji, and the latter team started to fight back.
While supporting her local team, the generous-hearted royal always recognises both sides' efforts in high-quality international matches, and being so athletic herself, understands the hard work it takes to succeed.
The Princess of Wales was seen formally greeting her stepmother-in-law as she and Prince William arrived in Windsor with Germany's President Frank-Walter Steinmeier
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