Dariusz Michalczewski

Michalczewski came up through Poland's state-run sports program as a boy and had a successful amateur career. He achieved an amateur record of 139–11–2 (89 KO). Highlights of his amateur career include:

Michalczewski was to come out of retirement to fight German boxing icon Sven Ottke in Germany in May 2008, but the bout never materialized.

In October 2004, it was announced that Michalczewski would come out of retirement to box France's Fabrice Tiozzo for the WBA light heavyweight title on 26 February 2005 in Hamburg. Michalczewski was stopped in six rounds, then announce his retirement in May 2005.

Michalczewski had a perfect record of 48-0 when he faced Julio César González of Mexico in defense of his title on 18 October 2003. Coming into the fight, he was within one victory of tying Rocky Marciano's record of 49 wins with no losses. A win also would have put him just one victory short of Joe Louis' all-time record for successful defenses at any weight class. However, as when Larry Holmes went for the same record against Michael Spinks, the now 35-year-old Michalczewski was unable to pull it off. He lost a controversial split decision to the 27-year-old Gonzalez at the Color Line Arena in Hamburg, and his career record dropped to 48-1.

In 2003 Dariusz Michalczewski established foundation "Równe Szanse" (equal chances) which was aimed at supporting initiatives for youth from dysfunctional families. Since 2014 he supports the social campaign for civil union and the right for adoption by homosexual couples.

After beating Hill, Michalczewski knocked out 14 consecutive opponents, all in defense of his Lineal/WBO titles. In 1998, he defeated Drake Thadzi, in 1999 he defeated Montel Griffin, and in 2000 he defeated Graciano Rocchigiani.

On 13 June 1997, he defeated Virgil Hill over 12 rounds to add Hill's WBA, IBF and Lineal light-heavyweight titles to his own. However, Michalczewski soon lost both alphabet titles. The WBA immediately stripped him for displaying its belt along with that of the WBO, an organization it didn't recognize. Michalczewski was then forced to relinquish the IBF title when he was unable to defend the title in a court-ordered defense against mandatory challenger William Guthrie within a little over a month after the bout with Hill.

In 1996, Universum Box-Promotion's conditioning coach Fritz Sdunek became head coach and replaced Chuck Talhami as Michalczewski's trainer, which resulted in a marked improvement in Michalczewski's performances.

On 10 September 1994, Michalczewski, at 23-0 (18 KOs), captured the WBO light-heavyweight title with a 12-round decision over defending champion Leeonzer Barber at Sporthalle, Alsterdorf, Hamburg, Germany. Between then and March 2003, Michalczewski made 23 successful defenses of his WBO title against 20 different boxers, and picked up three other belts along the way. Three months after beating Barber, he won the WBO cruiserweight title with a tenth-round knockout of Nestor Giovannini. However, he soon gave up that title to continue campaigning as a light-heavyweight.

Michalczewski turned professional in September 1991. He won the German International light-heavyweight title early on 13 February 1993, a title for foreign-born fighters based in Germany. He then won the IBF Intercontinental title on 22 May 1993.

On 24 April 1988, while competing beyond the Iron Curtain in West Germany for the Polish national team, Michalczewski defected from the amateur team to stay in West Germany. Becoming a citizen of the now united Germany in 1991 and turning professional the same year, he was soon signed by Universum Box-Promotion, one of the leading boxing promoters in Europe. His aggressive style earned him the nickname "Tiger".

Dariusz Michalczewski (born 5 May 1968) is a Polish-German former professional boxer who competed from 1991 to 2005. He held multiple world championships in two weight classes, including the WBA, IBF, WBO and lineal light-heavyweight titles between 1994 and 2003, and the WBO junior-heavyweight title from 1994 to 1995.