July 11, 2015 1:57 PM EDT

Harry Potter author and social media dynamo J.K. Rowling crafted the perfect response to a tweet that took a cheap shot at tennis champ Serena Williams on Saturday.

The offending Twitter user drew an angry backlash for suggesting that Williams was more famous for her body than, say, her victory at Wimbledon on Saturday or her five previous wins at the tournament or the fact that she once again holds all Grand Slam titles once. Rowling joined a chorus of angry responses, only she didn’t indulge in anger herself.

Game point, Rowling.

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