On November 3, 2001, the 32-year-old WBA (Super) and WBC super-lightweight champion, Kostya Tszyu (27-1, 22 KOs), and the 24-year-old IBF super-lightweight champion Zab Judah (27-0, 21 KOs) faced each other for the undisputed world championpionship.
Tszyu came in to the fight on a 9-fight win streak with a 78% KO rate, and was fighting after a gap of 4 months and 11 days. Judah was on a 27-fight win streak with a 77% KO rate, and fighting after a layoff of 4 months and 11 days.
Kostya Tszyu made very easy work of Zab Judah, stopping Judah via TKO in the 2nd. Tszyu improves his record to 28-1 (23 KOs), while Judah adds a loss to his record at 27-1.
On February 3, 2001, the 31-year-old WBC super-lightweight champion, Kostya Tszyu (25-1, 21 KOs), and the 30-year-old WBA (Super) super-lightweight champion Sharmba Mitchell (47-2, 28 KOs) met in a title-unification fight.
Tszyu came in to the fight on a 7-fight win streak with a 80% KO rate, and was fighting after a gap of 6 months and 5 days. Mitchell was on a 16-fight win streak with a 57% KO rate, and fighting after a layoff of 4 months and 18 days.
Sharmba Mitchell refused to continue the fight in the 7th round, and Kostya Tszyu is crowned the new WBA (Super) super-lightweight world champion. Tszyu improves his record to 26-1 (22 KOs), while Mitchell adds a loss to his record at 47-3.
On November 6, 2004, Kostya Tszyu and Sharmba Mitchell met again in a rematch.
Tszyu came in to the fight on a 12-fight win streak with a 77% KO rate, and was fighting after a gap of 1 year, 9 months, and 18 days. Mitchell was on a 8-fight win streak with a 51% KO rate, and fighting after a layoff of 2 months and 30 days.
Kostya Tszyu made easy work of Sharmba Mitchell in the rematch, stopping the challenger via TKO in the 3rd. Tszyu improves his record to 31-1 (25 KOs), while Mitchell adds a loss to his record at 55-4.
On July 29, 2000, the 30-year-old WBC super-lightweight world champion, Kostya Tszyu (24-1, 20 KOs), faced a 38-year-old Mexican boxer Julio César Chávez (103-4-2, 84 KOs), in a title defense fight.
Tszyu came in to the fight on a 6-fight win streak with a 80% KO rate, and was fighting after a gap of 5 months and 17 days. Chávez was on a 1-fight win streak with a 77% KO rate, and fighting after a layoff of 7 months and 11 days.
Kostya Tszyu stopped Julio César Chávez via TKO in the 6th round of the 12-round world-title fight, and successfully defended his WBC super-lightweight title. Tszyu improves his record to 25-1 (21 KOs), while Chávez adds a loss to his record at 103-5-2.
On August 21, 1999, 29-year-old Kostya Tszyu (22-1, 18 KOs) and 28-year-old Miguel Angel Gonzalez (43-1-1, 33 KOs) fought for the vacant WBC super-lightweight title.
Tszyu came in to the fight on a 4-fight win streak with a 78% KO rate, and was fighting after a gap of 8 months and 24 days. González was on a 1-fight win streak with a 73% KO rate, and fighting after a layoff of 1 year, 1 month, and 10 days.
Kostya Tszyu stopped Miguel Angel Gonzalez via TKO in the 10th round of the 12-round world-title fight. Tszyu improves his record to 23-1 (19 KOs), while González adds a loss to his record at 43-2-1.
On January 28, 1995, a 25-year-old Kostya Tszyu (13-0, 10 KOs) got a shot at the IBF super-lightweight title held by Jake Rodríguez.
Tszyu came in to the fight on a 13-fight win streak with a 76% KO rate, and was fighting after a gap of 4 months and 30 days.
Kostya Tszyu stopped the champion via TKO in the 6th round of the 12-round world-title fight, winning the first world title of his career, and is crowned the new IBF super-lightweight champion. Tszyu improves his record to 14-0 (11 KOs)
On January 19, 2003, the 33-year-old undisputed super-lightweight world champion, Kostya Tszyu (29-1, 23 KOs), faced a 36-year-old American boxer Jesse James Leija (43-5-2, 17 KOs) in an undisputed title defense fight.
Tszyu came in to the fight on a 11-fight win streak with a 76% KO rate, and was fighting after a gap of 8 months and 1 day. Leija was on a 3-fight win streak with a 34% KO rate, and fighting after a layoff of 1 year and 14 days.
The challenger refused to continue the fight in the 6th round, and Kostya Tszyu is crowned the new super-lightweight world champion. Tszyu improves his record to 30-1 (24 KOs), while Leija adds a loss to his record at 43-6-2.
On May 24, 1996, the 26-year-old IBF super-lightweight world champion, Kostya Tszyu (16-0, 12 KOs), faced Corey Johnson, in a title defense fight.
Tszyu came in to the fight on a 16-fight win streak with a 75% KO rate, and was fighting after a gap of 4 months and 4 days.
Kostya Tszyu stopped Corey Johnson via KO in the 4th round of the 12-round world-title fight, and successfully defended his IBF super-lightweight title. Tszyu improves his record to 17-0 (13 KOs)
On February 12, 2000, the 30-year-old WBC super-lightweight world champion, Kostya Tszyu (23-1, 19 KOs), faced Ahmed Santos, in a title defense fight.
Tszyu came in to the fight on a 5-fight win streak with a 79% KO rate, and was fighting after a gap of 5 months and 22 days.
Kostya Tszyu stopped Ahmed Santos via TKO in the 8th round of the 12-round world-title fight, and successfully defended his WBC super-lightweight title. Tszyu improves his record to 24-1 (20 KOs)
On September 14, 1996, the 26-year-old IBF super-lightweight world champion, Kostya Tszyu (17-0, 13 KOs), faced Jan Piet Bergman, in a title defense fight.
Tszyu came in to the fight on a 17-fight win streak with a 76% KO rate, and was fighting after a gap of 3 months and 21 days.
Kostya Tszyu stopped Jan Piet Bergman via KO in the 6th round of the 12-round world-title fight, and successfully defended his IBF super-lightweight title. Tszyu improves his record to 18-0 (14 KOs)