Jimmy Fallon Completely Loses It When Tina Fey Attempts to Impersonate Sofia Vergara

NBC

The comedian and her cleavage can't seem to nail the 'Modern Family' star's persona.

Tina Fey and her cleavage attempted to impersonate Sofia Vergara, but couldn't quite pull it off.

During Monday's Tonight Show, host Jimmy Fallon got Fey to play "First Impressions," even though she admitted that she "stinks" at impersonations.

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Fallon quipped that Fey has "one of the worst" Robert De Niro impressions he's ever seen. The 45-year-old Sisters star then attempted to imitate Jack Nicholson, but the host thought she might be trying to talk like Matthew McConaughey.

Fey also did her best to impersonate Sofia Vergara, and even pushed her cleavage together to look like the Modern Family vixen. "I can't even put them together and get one good one," she exclaimed.

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While Fey's Tonight Show impersonations are making the rounds on Twitter, the former 30 Rock star revealed to ET that fans shouldn't expect her on social media anytime soon.

"There's just not enough hours in the day for it really," she said. "I'm just waiting to be able to show my nipples. If I can't show my nipples, I don't want any part of it."