'You're An Idiot': J.K. Rowling Defends Serena Williams From Internet Troll

It seemed like the whole world was cheering for tennis superstar Serena Williams following her stunning Wimbledon victory.

Read: Serena Williams Was a TV No Show After Partying All Night

That was until an internet troll named Rob came along and tweeted: "Ironic then that main reason for her success is that she is built like a man.”

Well look out Rob, you may now be the most hated tennis fan on the planet.

None other than Harry Potter author J.K. Rowling, a monster Serena fan, went positively medieval. She posted two pics of Serena in a hot, sexy red dress and tweeted: 'Yeah, my husband looks just like this in a dress. You're an idiot.'

While Rob the internet troll duked it out with the world's most popular author, Serena had the last laugh when she appeared at a London gala in a stunning and very feminine floor length gown.

View: Serena Williams Get Served Espresso on the Court

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