Jimmy gets a little jealous as Shawn Mendes discusses his growing friendship with Justin Timberlake, and the "In My Blood" singer talks about how he wiped out in front of Dave Grohl during a concert.<br /><br />Subscribe NOW to The Tonight Show Starring Jimmy Fallon: <br /><br />Watch The Tonight Show Starring Jimmy Fallon Weeknights 11:35/10:35c<br />Get more Jimmy Fallon: <br />Follow Jimmy: <br />Like Jimmy: <br /><br />Get more The Tonight Show Starring Jimmy Fallon: <br />Follow The Tonight Show: <br />Like The Tonight Show: <br />The Tonight Show Tumblr: <br /><br />Get more NBC: <br />NBC YouTube: <br />Like NBC: <br />Follow NBC: <br />NBC Tumblr: <br />NBC Google+: <br /><br />The Tonight Show Starring Jimmy Fallon features hilarious highlights from the show including: comedy sketches, music parodies, celebrity interviews, ridiculous games, and, of course, Jimmy's Thank You Notes and hashtags! You'll also find behind the scenes videos and other great web exclusives.<br /><br />Shawn Mendes and Jimmy Argue Over Who Justin Timberlake Likes More<br /><br /><br />#FallonTonight<br />#ShawnMendes<br />#JimmyFallon
