And the sexy pair went head-to-head yesterday as they both opted for red trouser suits.
Rihanna might have been in London and Blake across the pond in New York, but the pair mirrored each others' fashion choices as they smartened up their looks in tailored outfits.
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[Related story: Rihanna rocks London at Hackney]
Rihanna hit London for a night out in a skinny-legged pair of trousers with a contrasting pink hemline and a blazer with matching detail on the lapel.
She teamed the structured suit with a pair of white lace-up brogues and nothing but a floral bra top underneath as she left her hotel for a night on the town.
Gossip Girl beauty Blake went for different accessories for her androgynous look - sexing up her straight-legged pair with black strappy Louboutins, a black top and matching hoop earrings.
Rihanna and Blake aren't the only girls to dabble in a bit of suited trouser action either.
Hollywood actress Cameron Diaz confidently hit the 'What To Expect When You're Expecting' premiere in a sharp white tailored suit.
Cameron posed alongside Girls Aloud star Cheryl Cole in the suited number - managing to look divine.
And British singer Rita Ora also hit the NME Awards back in February in a white tailored trouser suit.
The 'R.I.P' singer looked uber sexy as she posed in all white, with a nude pair of patent stilettos.