The Prince and Princess of Wales were guests of honour at the Wales vs England rugby match on Saturday – going head-to-head as they cheered on their respective teams.
As patron of the Welsh rugby union, William was there to cheer on Wales while his wife, patron of the Rugby Football Union, had her support firmly placed with England.
Watch the royal couple sing the Welsh national anthem
In the end, it was rugby fan Kate who emerged victorious, with England beating their rivals in Cardiff, 20-10.
After the match, both royals headed to the locker rooms to meet their teams. Photos were later shared on the couple's official Instagram account – and royal fans couldn't help but notice a surprising detail in one of Kate's snapshots.
One image shows the Princess sat next to Maro Itoje, laughing as he reaches towards someone taking a photo of the pair. Maro later shared the photos on social media - much to fans' delight.
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Kate poses for a photo with England rugby star Maro Itoje
"Is that a disposable camera in picture 2?!" one fan remarked with a second adding: "I spotted it too! Brings back some memories."
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A third had a possible explanation for the use of the retro camera. "Probably not allowed mobiles in private meetings for security reasons. Good idea if that is the reason, they can relax and be unguarded."
The royal couple shared photos from their day out on social media
Certainly, Kate seemed very happy and laid back in the snapshots. "Love how Kate just sits for photos like good mates do. She's the best!" one follower noted.
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A second added: "Bless her - all that sweaty testosterone in the dressing room - totally chilled and unfazed - she's a complete winner!" And a third simply stated: "Everyone always looks incredibly happy when speaking with Kate and Will."
Kate was in high spirits on match day
During their visit to the Principality Stadium, Kate lifted the lid on her children's sporty side during the pre-match reception.
The mother-of-three revealed how her eldest, Prince George, is levelling up his rugby skills at school. The nine-year-old is advancing from tag rugby to touch rugby and is learning how to tackle.
The royal couple went head-to-head, with Kate cheering on England
"They are trying to teach him the rules," Kate said, adding: "They move them around for their confidence. Because he is tall, he has the physique."
The Princess also spoke about George's siblings. "But then there is Louis coming. Charlotte also does rugby," she said.
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