The seven-year-old wore a suit and tie at the stadium despite stories that he might wear an England shirt on the night.
Wimbledon star Marion Bartoli said Prince William, who is president of the Football Association, wanted his son to wear a shirt for the game but the tennis champion added Kate wasn’t “so keen” on the idea.
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French tennis star Ms Bartoli shared the news while commentating for the men’s singles final between the number one Novak Djokovic and Matteo Berrettini.
Speaking on BBC Radio 5 Live, she said: “Yesterday I had an afternoon tea with the duchess and it was very much a discussion whether George will be allowed to wear the jersey tonight at Wembley or not.
“William was for it, Kate not so keen, so we’ll see.”
The duke, duchess and George sang God Save the Queen before kick-off.
Kate wore a white jacket with red earrings in support of the England team.
William and Kate clapped after Luke Shaw scored for England after just two minutes while George beamed with delight after the goal.
Earlier fans were treated to the sight of the Red Arrows flying over the stadium.
The Royal Airforce acrobatic team flew in formation trailing red, white and blue smoke over north London.
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