Though, technically, former heavyweight champion of the world Vitali Klitschko is merely stepping away from boxing for the time being to concentrate on his political career, there is a very strong chance that, at 42, the Ukrainian really is calling it a career.He and brother Wladimir, who currently holds every heavyweight world title other than the WBC edition his elder sibling has just vacated, are often ridiculed by critics for dominating an era of the sport at their weight class which has been a shell of what heavyweight fighting used to be.And yet, looking back at the decade-plus of Vitali's ring time, we cannot help but find countless memorable fights and moments nonetheless.So here is a look back at Doctor Ironfist's defining moments, and here's hoping he does indeed decide to return to the ring for a proper send-off at some point.(eurosport.com)ANN.Az