Lionel Messi's bodyguard showed off his own athleticism ... barreling onto the field mid-game to take down a fan -- and, it was all caught on video.
Messi's Inter Miami CF took on Sporting KC in Arrowhead Stadium Saturday night when an overexcited fan tried to snap a pic with LM while the game was in progress.
Check out the clip ... the fan comes running up to Messi while the ball's actually in play -- but Messi's man, Yassine Cheuko, gets there just as quick and barely leaves enough time for the dude to snap a selfie before he's thrown to the ground.