Taylor Swift's dance moves are the subject of many conversations following awards shows, but what you didn't know is that her epic moves started with Jimmy Fallon!

The country/pop star stopped by The Tonight Show Starring Jimmy Fallon on Tuesday night (Feb. 17), where she discovered that Fallon was a little upset with her.

"I gotta say I'm kind of a little upset," the host tells Swift in the clip above. "I'm a little upset every time I see you dancing at events, because for a while, that was our thing."

"Yeah, that was a long time ago, but we really used to go all out," the "Red" star responds compassionately. "I'm sorry I forgot about that being just our exclusive thing."

The two were what Fallon calls "famous Jumbotron dancers." They would go to sporting events around New York and give the camera their best silly dance moves, which would put them on the big screen. Thankfully, Fallon got ahold of the footage.

In between (real) clips of people shaking their groove things at sporting events, Fallon and Swift are decked out in team apparel, showing off their stuff. From the running man to the sprinkler to the "Cotton Eyed Joe," the pair did it all for the crowd.

The most amazing part? Swift says this 'lost footage' wasn't pre-taped. "I haven't changed clothes that fast since the tour ended," she writes on social media.

Swift proves yet again that she's not afraid to make fun of herself — and she'll need those dance moves to be well-practiced when she heads to London for a show on Feb. 25. The star will tour her 1989 album — her first official foray into pop — globally through 2015.

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