Shawn Mendes and James Corden Sing Off in Epic Cover Battle on 'Late Late Show'

The sketch was part of Mendes' week-long takeover of Corden's CBS late-night show, and as has been the case all week, the comedian was left feeling quite defeated.

When Mendes showed up at his usual spot on the subway platform, he found Corden already well into James Blunt's "You're Beautiful."

"I'm sorry, I'm sorry, excuse me," Corden interrupted the singer, who walked in on guitar, smashing a cover of Oasis' "Wonderwall."

"What do you think you're doing busking here? I'm already playing over there," Corden said.

Mendes assured Corden Wednesday morning was his usual time slot and said he wasn't leaving his spot, which meant one thing and one thing only -- game on.

The two ended up doing everything they could to establish their domain. As Mendes was finishing up "Wonderwall," Corden appeared with a grand piano to sing "Great Balls of Fire," but before he could finish the song, Mendes left and returned as "DJ Stitches." Dressed in a hoodie and sunglasses, DJ Stitches, his massive DJ booth and accompanying disco ball did everything they could to get the crowd hyped. Unfortunately, the cranky subway patrons weren't having it.

Corden raised the bar one more time, leaving and returning with four life-sized Backstreet Boys dolls to sing "Everybody," but it was game over when Mendes was lowered from the sky dressed as an angel to sing his own hit, "There's Nothing Holdin' Me Back."