Shawn Mendes Showed His Humorous Side On The Tonight Show

(Radio.com) As emotional as Shawn Mendes can be in his music, he knows how to cut loose and have a good time. Mendes joined The Roots last Thursday night (Sept. 22) on The Tonight Show Starring Jimmy Fallon to sing whimsical fall versions of songs, both new and classic.

But in between doing his bit, he couldn't help making fun of Fallon who loved every minute of the ribbing. Mendes sang new versions of Justin Bieber, Adele and Coldplay, among others. In between singing the newly written lines � presented as Fall-themed tweets � he couldn't help calling Fallon a "grandpa" and reminding the host about their age difference.

After Mendes sang an autumn-themed take on Simon and Garfunkel's "The Sound of Silence," he teased Fallon for giving him the wrong cue, which led to mocking Fallon's choice to use the song in the sketch. "I told you, I'm just not as old as you," Mendes said. Immediately, Fallon rebutted, "Son, don't talk back to your father like that!"

Mendes added, "You don't look old, you're fine. No, you're not� I'm just very young." After the comedy bit, Mendes performed his latest single "Mercy" off his sophomore album Illuminate. Watch the clips here.