It's Evelyn Lozada!
The Basketball Wives star and her friend Kandi Yams, a celebrity nail designer based in Los Angeles, both look ecstatic to be posing with Rihanna.
Evelyn posted the pic, writing, "With my boo @badgalriri & @kandiyamz - Rihanna did her thing! Luv her! Can u tell Kandi was excited to meet her idol? ☺"
Standing side by side, we do see a resemblance between Evelyn and Rihanna!
Did you guess who the mystery star was?