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Kate Middleton has wowed fashion designers, devoted herself to charity work, won the hearts of both the British public and its  prince, and now scored in yet another field: athletics.

The Duchess of Cambridge showed off her sporty side today in a surprise visit to the Olympic Park in Stratford, East London, the site of the London Olympics this summer,  for which   Middleton and her husband, Prince William, have been named ambassadors.

While Middleton arrived at the Olympic site looking fashionable in skintight coral jeans and a navy blazer over a white top accented by an Olympic scarf around her neck, it didn't take long for her to kick off her trademark high heels for a cause close to her heart.

In her role as ambassador, Middleton, 30, had made a special request to meet with members of the British Olympic women's field hockey team, according to the BBC.

For that occasion, she laced up her sneakers and ditched the formal blazer for a gray "Team GB" (Great Britain) sweatshirt while keeping her jeans, identified by British fashion bloggers as $370 J Brand coral twill skinnies.

Taking the field with the team, Middleton modestly expressed some doubts about her  field hockey ability, even though she served as captain of  the hockey team in high school at Marlborough College.

"This is going to be so embarrassing," she said. "My brain thinks I can do all these wonderful things, but my body just doesn't play ball."

Once again, however, Middleton proved there really might be nothing she cannot do.

Given a stick, the duchess took a swing and sent the ball straight into the, albeit unguarded, net.

"She told me that she used to hit the penalty corners, and you could see that," Kate Walsh, the Olympic team captain, said of Middleton's skills.  "She got low and her shots were really sweet."

Later in the day, Middleton accompanied her father-in-law, Prince Charles, and stepmother-in law, Camilla, Duchess of Cornwall, to an art museum to see the work of Charles' Foundation for Children and the Arts, one of the charitable causes to which she's committed.

For that occasion, Middleton wore a gray pleated dress by Irish designer Orla Kiely, according to British fashion watchers.

Middleton has been in the spotlight  lately,  making a series of solo appearances to celebrate her charity work, and  the queen's 60 years on the throne, while Prince William completes a six-week deployment to the Falkland Islands for his Royal Air Force search-and-rescue duties.

Earlier this month, Middleton made her first solo appearance with the queen and Camilla, stepping out for tea at the luxury London department store Fortnum & Mason.

The Associated Press contributed to this report.