"Justin Bieber is tough, for real. What, you don't believe him? You want to fight about it?"

Maybe that's the train of thought that led Bieber to seek out boxing lessons from Floyd Mayweather. The singer's winning combination of polarizing celebrity and escalating legal trouble would seem to increase his odds of finding himself in fisticuffs, and exercise is a great way to de-scrawny a body.

What's less clear is why Mayweather, a five-division world champion and undefeated as a professional boxer, would want to teach Bieber how to swing his fists at people who make him mad.

But the two apparently have a years-long friendship -- or something like that -- during which the pop star has sat ringside at Mayweather fights on several occasions.

All of this to say that some questions don't have answers. Nevertheless, there's video proof that the Mayweather-Bieber training sesh happened:


Sure, Bieber, you can swivel your shoulders real nice and flex those tatted biceps. But how well do you take a fist to the face?

That's a video we'd like to see.

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