Serena Williams and 'OITNB' Star Laverne Cox Sing Karaoke

Serena Williams traded in her tennis racket for a microphone on Wednesday night, as she performed at a karaoke event for Delta Airlines along with Orange Is The New Black star Laverne Cox.

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"I love to karaoke," Serena said at Arena in New York City. "I'm not a good singer, but that's what karaoke's about. It's about those people who had dreams of singing, but can't even hold a tune."

Laverne is such a big karaoke fan that she tries to do it at least once a month.

"I get together with a group of my friends and we rent a room and we're usually there for two or three hours," said Laverne. "Karaoke is sort of my cathartic, creative release that's not about work."

Tennis player Jack Sock, Orange Is The New Black's Uzo Aduba, Glee star Darren Criss and comedienne Kathy Griffin also attended the event.

Watch the video to see Serena belt out "Diamonds Are a Girl's Best Friend" and Laverne give a special rendition of Whitney Houston's "One Moment in Time."