Klitschko brothers 5 months & 13 days. Vitali retained the WBC Heavyweight Championship until 15 December 2013, relinquishing his belt in pursuit of his political aspirations in his native Ukraine. The Klitschko brothers jointly run the professional boxing promotion companies ""K2 Promotions"" and ""K2 East Promotions"", as well as the ""Klitschko Brothers Fund"", a charity organization. They appear together on German TV shows and commercials, have a website shared between them, and support each other's training and fights. After Vitali's retirement, Wladimir continued to reign as champion & successfully defend all remaining title belts except for the WBC belt. He eventually lost
Wladimir Klitschko out of the fight due to not being fully recovered from a torn abdominal muscle. On 5 March, it was instead announced that the highly anticipated fight against David Haye would take place on 2 July 2011. The fight was contingent on Klitschko's recovery from a torn abdominal muscle injury. The contract was written so that if Klitschko was not fully healed, then Haye would fight his brother, Vitali. Klitschko fought David Haye in a heavyweight unification fight for the WBA (Super), WBO, IBF, IBO and "The Ring" Heavyweight titles. The fight took place at the Imtech Arena, Hamburg, Germany