Serena Williams Comes Clean About Her Cameo in Beyonce's 'Sorry' Video

The tennis star surprised fans when she appeared dancing alongside Beyonce.

ByABC News
June 20, 2016, 4:39 PM
Serena Williams attends the premiere of EPIX original documentary "Serena" at SVA Theater, June 13, 2016, in New York.
Serena Williams attends the premiere of EPIX original documentary "Serena" at SVA Theater, June 13, 2016, in New York.
Andrew Toth/Getty Images

— -- Serena Williams surprised a lot of folks, including her close friend and fellow competitor Caroline Wozniacki, when she popped up in Beyonce's music video "Sorry."

"I've known Bey for a long time," Williams told WSJ., the Wall Street Journal's magazine.

In the video, Williams dances alongside the pop star.

The tennis star confessed to the magazine, which features her on the cover, "I got really sore from dancing!"

She added that she had to stay mum about the project for months.

"If you tell me, 'Don't say anything,' I won't say anything," Williams said.

Wozniacki can vouch for that. "She really kept it a secret," said Wozniacki, who didn’t know about Williams' involvement in the video until she saw it.

"Sorry," about an apparently unfaithful man and his mistress, is best known for its line, "He better call Becky with the good hair."

Although Williams was happy to appear in the video for the song, her favorite song to dance to is far more vintage: "Conga," by Gloria Estefan and Miami Sound Machine.