Game, set, fashion match.

Kate Middleton looked sporty in tennis gear yesterday as she joined tennis great Roger Federer for a YouTube video highlighting the work of Wimbledon’s ball boys and girls.

The Princess of Wales, 41, serves as patron of the All England Lawn Tennis and Croquet Club, which hosts the tennis tournament — and she showed her team spirit in branded Wimbledon merch ahead of the 2023 championships.

In the video, the royal wears a white sleeveless polo ($83) trimmed with the Wimbledon colors of green and purple along with a white Adidas x Stella McCartney tennis skort and $24 gold chain hoops by Orelia.

The princess — who is an avid tennis fan as well as a player — held her own against Federer on the court as she played in a pair of $205 Babolat Jet Mach 3 sneakers.

She wore her hair in a bouncy high ponytail and covered up her polo at one point with a zip-front white jacket ($190) trimmed with the Wimbledon colors.

The mom of three also took part in some training exercises, learning how the ball girls and boys of Wimbledon prepare for their roles — and getting gently rebuffed for catching a ball when she wasn’t supposed to in a now-viral clip.

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“The #Wimbledon Ball Boys and Girls play a pivotal role in The Championships,” Middleton captioned a series of Instagram snaps. “We went to visit them on a day’s training with @rogerfederer.”

The future queen has been a Wimbledon regular over the years — even before she took over its patronage from Queen Elizabeth in 2016 — sporting a series of standout looks at every championship series.

From blue-and-white dots to lemon-yellow looks, she never fails to hit the court in a winning outfit.

Stay tuned for all of the royal fashion hits when this year’s Wimbledon championships start on July 3.