Don't touch the merchandise.
Justin Bieber delivered that message loud and clear on his way into his Barcelona show Tuesday night when a fan reached through the rolled-down rear window of the pop star's chauffeured ride as it rolled past and tried to touch the Biebs' face.
Running alongside the car as it headed toward the venue, the fan managed to tap Bieber on the chest and reached toward his face.
The "Sorry" singer then punched the guy, leaving the fan's face bloody from a split lip. TMZ has video of the altercation, which in addition to the blood includes an awful lot of high-pitched squealing. The girls around split-lip guy seem excited at first, before their expressions change to major "OMG."
"I touched his face like this and he went, 'Boom,'" the fan said, according to a Mirror translation.
And that's what happens when you get handsy with a guy trained to fight by Floyd Mayweather Jr.
By his own account, Bieber had had a "great day" in Barcelona on Monday, hanging out on the soccer field with Neymar, Luis Suarez and Leo Messi from FC Barcelona.
He's set to perform Wednesday night in Madrid, where, according to Spanish news service EFE, more than 1,000 fans were already waiting in line at the beginning of the day — hopefully keeping their hands to themselves.
Follow Christie D'Zurilla on Twitter @theCDZ.