Here’s a word to the wise: if you ever find yourself outside Justin Bieber’s car and feel the urge to stick your hand through the window in order to give him a grab, expect to spend the next few hours in the emergency room.

That’s what a pushy fan in Barcelona learned the hard way when he thrust his hand through the open car window in an attempt to grab himself a handful of Biebs, reports TMZ, instead winding up with a mouthful of knuckles, courtesy of the “Purpose” singer.

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The punch, notes TMZ, would have done Floyd Mayweather proud, reporting that “the guy ended up a bloody mess as he and his friends reacted in shock” — and there’s even video to prove it.

Justin Bieber is currently in Europe on his Purpose World Tour, where just a few days earlier he suffered the indignity of having an overzealous fan in Prague pull down his pants while he was leaving a building — let this be a warning to European Beliebers to keep their hands to themselves.

The fan, 18-year-old Kevin Ramirez, says he is “disappointed” and “very hurt” by the singer and plans to take legal action: “This matter is now in the hands of lawyers. They will deal with it. I can’t give out any more information at the moment,” Daily Mail reports.