The “Inventing Anna” actor, 50, was in the stands as Serena Williams faced off against Danka Kovinic, sporting a black face mask, a low ponytail, and hoop earrings.

While some people recognized her as a former star of “Orange Is the New Black,” at least one person thought she was a different celebrity altogether.

#Beyoncé at the #USOpen,” Twitter user @Choni_captioned footage of Cox cheering on Williams at the USTA Billie Jean King National Tennis Center in New York City. Later, after the tweet gained traction, the user added, “My bad. I wasn’t trying to be funny I promise.”

Cue the flood of tweets from fans setting the record straight.

“Baby. That’s Laverne Cox,” one person wrote.

“The fact that this is Laverne Cox has me screaming,” another person tweeted.

“I know Laverne Cox is cocky as hell right now,” another person wrote, along with multiple cry-laughing emoji, “and should be cuz if I got mistaken for Beyonce on national television I would never shut up.”

As fans predicted, Cox was nothing but amused by the case of mistaken identity, and by people’s reactions to the mixup.

“Not me getting mistaken for @Beyonce at the #USOpen tonight then trending on Twitter as the internet cackles over the mistaken identity,” Cox wrote on Instagram, sharing footage of herself at the match. “These tweets are funny as hell. Enjoy!!!”

Cox also noted that she took the mixup as nothing but a compliment.

 “Absolutely!” she wrote to a fan who tweeted, “2nd biggest winner tonight: Laverne Cox who was mistaken for Beyonce all night. Which is a career highlight for literally anyone.”

Cox herself is a confirmed member of the Beyhive. Back in 2017, she could hardly contain her excitement when she met the singer, whose most recent album came out this summer, at the Grammys.

 “This finally happened,” Cox captioned a pic of them posing together on Instagram. “I was so beside myself with joy, wonderment, and awe of the majestic that is the queen I forgot to hold in my stomach and give you face. But I met #QueenBey y’all.”