Big Harry Potter fan? John Legend accidentally referred to La La Land costar J.K. Simmons as J.K. Rowling on the SAG Awards red carpet on Sunday, January 29. 

The Grammy winner, 38, was talking to E!’s Giuliana Rancic about getting the chance to work alongside costars such as Ryan Gosling and Emma Stone when he accidentally gave the Harry Potter author a shout-out.

“Most of your scenes … are with Ryan Gosling … what did you learn from him?” Rancic asked the singer, who plays jazz musician Keith in the Oscar-nominated musical, which he also executive produced. 

“I was impressed with him because he had to look like [he played the piano] … and then I was just humbled to be in the presence of such greatness,” Legend said. “I mean, he’s obviously an experienced actor. Emma is an experienced actor. We got J.K. Rowling,” he added, before quickly correcting himself. “Simmons — not Rowling — and so many great people in the film and I’m just happy to be a part of it.” 

Twitter, of course, was quick to pick up on the live TV snafu. 

“@chrissyteigen @johnlegend must LOVE Harry Potter 😂 #JKRowling,” one person on Twitter wrote, while another added: “Awww @johnlegend accidentally said @jk_rowling instead of JK Simmons on the red carpet. Harry Potter on the brain! ⚡️.”

Legend, who is presenting at the awards show tonight, laughed off the blooper and went on to tell Rancic about his adorable 9-month-old daughter, Luna, with wife Chrissy Tiegen.

Watch the moment above.  

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