Harry Potter author and tennis fan J.K. Rowling took to Twitter on Saturday to congratulate Serena Williams on her sixth Wimbledon win.

But things got ugly really fast.

Here’s the tweet that Rowling sent out first.

And then some Twitter body-shamer named Rob tweeted that Serena is built like a man, which provoked Rowling to tweet this:

Which just unleashed an avalanche of more head-shaking troll activity like this:

Then Williams showed up at Sunday’s Wimbledon Champion’s Dinner in a glamorous form-fitting gown, which she showed off on Instagram.

Take that, trolls.

Then Williams and Wimbledon men’s champion Novak Djokovic won the crowd with a charmingly awkward turn on the stage to “Night Fever.”

Yeah, winning.