Justin Biebermay be winning chart battles across the world, but the pint-sized popstar may have bitten off more than he can chew when it comes to his latest contender.
The 17-year old has been spotted in the boxing ring with none other than World Heavyweight Champion David Haye, after the boxer invited the Biebster to train with him at his gym in Vauxhall.

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Despite JB being half Haye's weight and being a foot smaller that David, the teenage heartthrob is said to have put in a few punches against the 6"3 boxer.
A source told Craig Davidfor an unlikely duet.
After teaming up with Bieber, Craig tweeted: "Great performing with @justinbieber tonight at his show at the o2!"