'Grey's Anatomy' Cast: Blue Is the New Black

Who knew the Grey's Anatomy stars were such Orange Is the New Black fans?!

Before there were prison uniforms and sex scenes behind bars, there were blue scrubs and locker room love scenes. Though Grey's got to TV long before OITNB, the cast is using the Netflix show's recent momentum to promote their own new season.

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Leading lady Ellen Pompeo posted on both Instagram and WhoSay on Wednesday, Sept. 17, a pic of her posed with her co-stars as the cast of OITNB -- only with one big difference. They're all wearing Grey's trademark blue.

Pompeo wrote: "Blue is the new black #8daystillgreys #greysanatomy."

When asked by a Twitter follower if she watched the women's prison dramedy, Pompeo wrote: "Those girls are giving it."

Season 11 of Grey's Anatomy premieres on Thursday, Sept. 25 at 8 p.m. ET. That being said, there is no planned crossover with OITNB.

Which program do you prefer? Stand by your show in the comments and tweet us at #ETnow.

While we wait for Grey's big premiere, see why the show's stars would make horrible doctors in real life.