Factbox: Former heavyweight world champion Wladimir Klitschko
(Reuters) - Factbox on former heavyweight world champion Wladimir Klitschko, who announced his retirement from boxing on Thursday.
Born: March 25, 1976 Semipalatinsk, Kazakhstan (Age 41)
Win-loss record: 64-5 (53 knockouts)
* Won gold medal at junior European championships in Thessaloniki as a heavyweight in 1993. Claimed silver at the junior world championships in Istanbul a year later.
* Won gold medal at the 1996 Olympics in the super-heavyweight division as an amateur.
* Turned professional in 1996.
* Built an undefeated record of 24-0 with 22 knockouts before suffering his first loss to Ross Puritty in Klitschko's only professional bout in Ukraine.
* Defeated American Chris Byrd in 2000 to win the WBO heavyweight title. His reign ended with a defeat to Corrie Sanders in 2003.
* Regained the IBF and IBO titles in a rematch with Byrd in 2006.
* Won the WBO title for the second time by defeating Russian Sultan Ibragimov in 2008.
* Was awarded the Ring and lineal titles with a victory over Uzbekistan's Ruslan Chagaev in 2009.
* Won the WBA title from Briton David Haye in 2011.
* Went undefeated for 11 years before losing his WBA, IBF and WBO titles to Tyson Fury in November 2015.
* Knocked out in the 11th round by current champion Anthony Joshua at Wembley in April.
* Fought in 29 heavyweight title fights, more than any heavyweight champion in the sport's history.
(Compiled by Hardik Vyas in Bengaluru)