Ellen DeGeneres, Jimmy Fallon Shut It Down With Best Lip Sync Battle Ever: Video

Ellen DeGeneres and Jimmy Fallon faced off in the most epic Lip Sync Battle ever on Wednesday, Sept. 9 -- watch here. Credit: Douglas Gorenstein/NBC/NBCU Photo Bank via Getty Images

Oh Jimmy Fallon, do you know... who you're dealing with? Ellen DeGeneres and the Tonight Show host faced off in an amazing new Lip Sync Battle on Wednesday, Sept. 9, and both TV personalities shut it down.

Fallon, 40, warmed up the segment with his lip sync of The Killers' smash single, "Mr. Brightside."

DeGeneres, 57, then followed up with a more low-key tune, hilariously executing her cross-legged, sad, and sultry rendition of Diana Ross' 1975 song "Do You Know Where You're Going To."

While Fallon and guest Justin Timberlake cracked up on the sidelines, DeGeneres reveled in the spotlight and expertly crooned the slow hit. That's when things got intense.

Fallon attempted to woo the audience by performing one of the songs of summer 2015, "Watch Me (Whip/Nae Nae)" by Silento, which was countered by DeGeneres lip-syncing to Rihanna's "Bitch Better Have My Money."

Just like Us, the judge of the competition, Timberlake, knew that DeGeneres won the battle, but all was good between him and Fallon. After Wednesday's taping, the two eventually made their way over to Arthur Ashe Stadium in NYC for the US Open, where they busted out their dance moves to Beyonce's "Single Ladies."

Put your hands up! And watch DeGeneres' Lip Sync Battle above!

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