The Swiss former world number one played a bit of tennis and some ten-pin bowling-inspired games, designed to increase accuracy.

Alongside the princess, Federer also took the time to chat about training and expectations of Wimbledon with the youngsters.

A ball boy himself, once upon a time, Federer was put through his paces alongside those who will be present at the SW19 Grand Slam over the next two weeks.

"This is proper practice, I'm really impressed," remarked the retired veteran of the game to Kate.

Take a watch of the full video on Flashscore below, which also includes interviews with some of Wimbledon's trainers and key decision-makers.