Wladimir Wladimirowitsch Klitschko is a Ukrainian former professional boxer who competed from 1996 to 2017. He held the world heavyweight championship twice, including the unified WBA (Super), IBF, WBO, IBO, and Ring magazine titles. A strategic and intelligent boxer, Klitschko is considered to be one of the best heavyweight champions of all time. He was known for his exceptional knockout power, using a strong jab, straight right hand and left hook, as well as great footwork and mobility, unusual for boxers of his size.