Wladimir Klitschko (born 25 March 1976) is a Ukrainian heavyweight professional boxer. Klitschko is the WBA (Super), IBF, WBO, IBO and The Ring Heavyweight Champion, and is the younger brother of WBC Heavyweight Champion Vitali Klitschko. Klitschko is the longest reigning IBF, WBO & IBO Heavyweight Champion in history with the most title defenses for those organizations. Overall, he is the 2nd longest reigning Heavyweight Champion of all time with the 3rd most successful title defenses at 15. On the 13th October 2013, Boxrec rated Klitschko as the number 2 pound-for-pound fighter in the world. Ring Magazine currently rates Klitschko as the number four pound-for-pound boxer in the world. Klitschko (22–2) is no. 3 on the all time list for most heavyweight title fights, only behind Joe Louis (26–1) & Muhammad Ali (24–3).
Since 2005, Klitschko has been the dominant force in the heavyweight division, defeating a majority of the top heavyweights in the rankings. When Klitschko won the IBF title against Chris Byrd there were four separate Heavyweight Champions. Since then, he has unified the IBF, IBO, WBO & WBA belts and defeated the WBA Champion in recess. Following his win over Ruslan Chagaev, Klitschko was awarded the vacant Ring Magazine Heavyweight title.