A video posted by Taylor Swift (@taylorswift) on

Taylor Swift celebrated her massive week of '1989' sales just like any other pop star would -- by rapping along to Kendrick Lamar's 'Backseat Freestyle.'

In Taylor's Rolling Stone profile, published earlier this year, the singer raved about the hip-hop star's song, proclaiming, "This is my go-to." It's no surprise then that the 'Shake It Off' singer knew every word of the track as she lip synced along.

After the story was published, Kendrick applauded Taylor for supporting the musical genre.

“I appreciate Taylor Swift for supporting not only my music but just the hip-hop culture,” he fifth annual ONE Musicfest in Atlanta on Sept. 13. (Quote via Billboard.) “There’s really no gap. It’s music and it feels good.”

Kendrick once more discussed Taylor's musical choices in an interview with the Fader.

"Shout out to Taylor Swift," he said. "You can't put great music in different genres. I enjoy great music outside of my own music all the time, so I definitely can see where she's coming from when she says that she listens to the record, and it's a great thing for her to acknowledge that and put that good energy out into the world like that."

You can watch Taylor rock out to Kendrick's 'Backstreet Freestyle' in the video above.

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