Justin Bieber bizarrely challenges Tom Cruise to an MMA fight nobody asked for

Biebs, for the hundredth time...you alright, bud?

For reasons best known to himself, everybody's favourite boy-racing, banger-machine Justin Bieber has decided to challenge Tom Cruise to a round of fisticuffs.

Possibly bored with a life of fast cars, public breakdowns and routinely burning his Calvin Klein undies after only one wear, Bieber says he's now keen to take on the Mission Impossible star.

"I wanna challenge Tom Cruise to fight in the octagon," the 'Sorry' hit maker tweeted.

"Tom if you don't take this fight your [sic] scared and you will never live it down."

Pragmatic as always, the 25-year-old popstar is already thinking about the logistics of the bizarre showdown, asking Ultimate Fighting Champion president Dana White to host the match.

"Literally, what?" one fan tweeted, speaking on behalf of just about everyone.

Others quite rightly pointed out that Cruise, 56, is famous for risking his life to do all his own stunt work, and likely has little to gain from beating up the boy who brought us those seminal lyrics "baby, baby, baby, oh".

Not everyone's a cynic, however - notorious former UFC champion Conor McGregor appears positively tickled by the idea, and he's keen to roll his sleeves up to make it happen.

"If Tom Cruise is man enough to accept this challenge, McGregor Sports and Entertainment will host the bout," McGregor tweeted.

"Does Cruise have the sprouts to fight, like he does in the movies? Stay tuned to find out!"

Don't have to tell us twice, Con.

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