When "The Tonight Show" host told the singer that he was jealous of her always getting down in the audience of award shows, he reminded her that it was something they used to exclusively do at New York sporting events.
"Yeah, we used to go to the sporting events in New York and really just give it our all," the 24-year-old said.
"We contacted a lot of arenas around New York and we actually got some footage. Of just Jumbotron footage, just random footage... we're actually a lot of it," he added.
Cue the dance-cam montage!
Fallon, who celebrated his first year as host of "The Tonight Show," ran some memorable dance-cam moments that were punctuated with him and the "Shake It Off" singer losing their minds when the camera singled them out.
Popcorn. Got. Everywhere.
The pair did a little Robot, sprinkler, catch the fish, board-breaking and running man at mock Knicks, Nets and Islanders games, finishing off with an ode to "Flashdance" at a Rangers game that you have to see for yourself.
The "Blank Space" singer covers the March issue of Vogue with bestie Karlie Kloss and also tried her hand at creating a portrait of Fallon without looking, much as she and Kloss did on the Vogue website.
Swift and Fallon both appeared on Sunday's "SNL 40." Fallon opened the show with pal Justin Timberlake and Swift took a turn as an oddly accented California girl in the star-studded "The Californians" SOAPnet sketch, alongside Kristen Wiig, Bill Hader, Fred Armisen, Kerry Washington, Betty White and Bradley Cooper.
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