Wladimir Klitschko is a Ukrainian former professional boxer who competed from 1996 to 2017. He is a two-time world heavyweight champion, having held the WBA (Super), IBF and WBO titles, as well as the IBO, Ring magazine, and lineal titles. A strategic and intelligent boxer, Klitschko is considered to be one of the greatest heavyweight champions of all time. He was known for his exceptional knockout power, using a strong jab, straight right hand and left hook.