Jason Derulo knocked out by Evander Holyfield as they spar in the boxing ring

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Jason Derulo was seeing stars this weekend and not the celebrity kind, after sparring with Evander Holyfield in the boxing ring. The Cats actor put the gloves on and went fist to fist with Evander, former heavyweight champion and notably remembered for having his ear bitten off by Mike Tyson during a fight. So Jason had a big job to do in proving he had the chops to take on a b