As one of Serena Williams' fans put it, "Can't stop, won't stop!"

On Thursday, the pregnant tennis pro posted a video to Instagram of herself in a practice match, and needless to say, she still slays. Dressed in an all-black outfit, Serena's growing baby bump was very visible as she fiercely hit the ball to her opponent.

WATCH: Pregnant Serena Williams Looks Fabulous While Babymooning in Monaco

The 35-year-old athlete might have been inspired to get back out on the court after attending sister Venus Williams' match at the French Open earlier this month. Serena was dressed in a chic black dress and silk floral robe as she watched her older sibling beat Elisa Mertens of Belgium during the Women's Singles round three match on Philippe-Chatrier Court at Roland Garros.

Serena recently had to clarify some comments made by Venus, where she implied that her sister was expecting a baby girl. The mom-to-be made it known that neither she nor her fiance, Alexis Ohanian, knew the sex yet.

WATCH: Pregnant Serena Williams Shows Growing Baby Bump in American Flag Swimsuit

"I think the surprise of knowing what you are going to have on that very special day you give birth is prob the best surprise you can ever have!" she wrote on Instagram. "So to clarify what Venus said, I am always joking with my sisters to see what favors I can get them to do for me next. If I want something from one of my sisters, I say, 'Baby Venus,' 'Baby Lyn,' or 'Baby Isha' needs it."

WATCH: Serena Williams Shows Off Baby Bump with Fiance Alexis Ohanian at 2017 Met Gala

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