Justin Bieber has been taught to box by former world heavyweight champion Mike Tyson. The 18-year-old pop star put his pugilistic skills to the test while visiting the 45-year-old retired sportsman - who famously once bit part of opponent Evander Holyfield’s ear off during a match - in Las Vegas last weekend, and Tyson took to his twitter account to post pictures of the pair in action. The ex-boxer posted an image of him, the ‘Boyfriend’ hitmaker and director Alfredo Flores as well as another snap of the pair and RockLive CEO John Shahidi. In a message accompanying the first picture, he wrote: ‘’Nice hanging out with @justinbieber &@alfredoflores (sic)’’ Mike also posted a YouTube video of Justin - who is known to be a big fan of champion boxer Floyd Mayweather Jr. - pounding his fists into a punch bag that the boxing legend is holding, and afterwards the pair high-fived each other. In a description of the clip on his YouTube page, Mike wrote: ‘’Justin swung by my place during the weekend of the Billboard Music Awards to say hi to the family.                   –ES