Looks like Biebs is taking this Celebrity Death Match between himself and Orlando Bloom fierce serious. Not that he wants us to think he's actually learning to box, or anything.

This video, which he posted to Instagram, is captioned: "Not a boxer but it's cardio and it's fun so don't judge me lol." Sure it's all fun 'n games until someone gets sucker punched in the stomach, hah?!

Might be an idea to take up Forrest Griffin on his benevolent offer of training, Mr Bloom. 

According to cambio.com, Justin also posted the below photo of what appears to him cradling Selena Gomez, entitled "Right now everything else is a blur" (that'd be after all the cardio, Justin). So blurry is the situation that Bieber deleted the pic shortly after. The usual.


 

In a typically mature move, Justin Bieber taunts Orlando Bloom via Instagram