(The relevant match starts at 8:57)Even if you're used to winning, you should never let your guard down.Chess Grandmaster Max Dlugy recently learned this lesson the hard way, falling for online chess player TrickyMate's trick in the opening moves of a game. He loses his queen almost immediately, realizes he is about to be checkmated shortly after, and resigns. For those (like me) who were a bit lost by the video, Reddit user petrichorE6 explains in more detail exactly what happened.The video is making the rounds among chess fans, because Dlugy loses only because he failed to take his opponent seriously. As petrichorE6 sums up: "It's not that the trick was that good, it's just that the Grandmaster took TrickyMate lightly and gave up on his Queen." Being a Grandmaster, you can't really blame him for being so confident, and Dlugy seems like a genuinely nice guy who takes his loss in stride as an almost pleasant surprise.Dlugy has been a Grandmaster since 1986 and specializes in speed chess, where each player has less time to contemplate their moves. (Regular tournament games have time limits of 60 to 180 minutes; blitz chess shaves this down to ten.) So even though he lost this match, he's still better at chess than you are. Don't get any ideas.