Dariusz Michalczewski (born 5 May 1968, in Gdańsk, Poland) is a German-Polish boxer and former light heavyweight champion.
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 133-15-2 (83 KO's). Highlights of his amateur career include:
On 24 April 1988, while competing in Germany for the Polish national team, Michalczewski defected from the team to stay in Germany. Becoming a citizen of 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 "The Tiger."
He won the German international light heavyweight (175-pound) title early on 13 February 1993, the title is for foreign born fighters based in Germany. He then won the IBF Intercontinental championship on 22 May 1993. Finally, on 10 September 1994, Michalczewski captured the WBO light heavyweight title with a 12-round decision over defending champion Leeonzer Barber.
Between then and March 2003, Michalczewski made 23 successful defenses of his WBO title and picked up three other belts along the way. Three months after beating Barber, he won the WBO's cruiserweight title with a knockout of Nestor Giovannini. However, he soon gave up that title to continue campaigning as a light heavyweight.
On 13 June 1997, he defeated Virgil Hill over 7 rounds to add Hill's WBA and IBF titles to his own. However, Michalczewski soon lost both alphabet titles. The WBA stripped him for displaying its belt along with that of the WBO, an organization it didn't recognize. The IBF did so a few weeks later, when Michalczewski refused to defend his title against mandatory challenger William Guthrie within 30 days.
After beating Hill, Michalczewski knocked out 14 consecutive opponents, all in defense of his WBO titles. On 1998, he defeated Drake Thadzi and in 2000 he went to defeat Graciano Rocchigiani.
Michalczewski had a perfect record of 48 wins and no losses 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 all-time record for an undefeated record by a world championship boxer. 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, 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.
Despite the loss, he still holds the record for the most consecutive successful title defenses at light heavyweight.
In October 2004, it was announced that Michalczewski would come out of retirement to fight France's Fabrice Tiozzo for the WBA light-heavyweight title on 26 February 2005, in Hamburg. He fought him but he lost, and then he declared the end of his career in May 2005.
Michalczewski was to come out of retirement to fight German boxing icon Sven Ottke in Germany in May 2008, but the bout never materialized.