Matt Damon employed some clever costuming and Super Bowl fever to sneak onto Jimmy Kimmel Live on Monday, posing as New England Patriots quarterback and Super Bowl MVP Tom Brady.
Damon came out decked out in Brady's jersey and rocking his football helmet, but it was clear the ruse wasn't going to hold up -- mostly because you could still see Damon's face, and he didn't alter his voice at all.
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After Kimmel pulled the helmet off, the audience went wild, cheering for the Great Wall actor uproariously as an annoyed Kimmel tried to get them to calm down.
"Touchdown!" an extremely amped up Damon yelled at Kimmel. "I won the Super Bowl and I won your stupid show!"
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Kimmel told Damon that his stunt didn't count as being a guest on the show because he didn't sit down on the couch, and then had Damon forcibly removed by security. However, that didn't seem to put a damper on the star's mood.
Sports reporter Rich Eisen caught up with Damon in the JKL dressing room -- which was covered floor-to-ceiling in plastic -- as he shook up some celebratory champagne to commemorate his big win.
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While Brady never actually made an appearance on Kimmel's show, the MVP's coach, Bill Belichick, and teammate, Julian Edelman, were in New York, sitting down with Jimmy Fallon.
Kimmel and Damon's long-running (and fictitious) feud has been an endless well of comedy for the late night host, who has been sparring with the Oscar winner since his show began.
Last February, Damon made it onto JKL yet again when his bestie, Ben Affleck, smuggled him into the studio inside a trench coat, only to pop out, mid-interview. Check out the video below to see the bizarrely hilarious moment.