Konstantin Borisovich "Kostya" Tszyu ( KOS-tə ZOO; Russian: Константин Борисович «Костя» Цзю, IPA: [kənstɐnʲˈtʲin bɐˈrisəvʲɪtɕ ˈkosʲtʲə ˈdzːʲu]; born 19 September 1969) is a Russian-Australian former professional boxer who competed from 1992 to 2005. He held multiple world championships in the light-welterweight division, including the undisputed and lineal championships between 2001 and 2005. Tszyu was an exceptional all-around boxer-puncher who relied heavily on accuracy, timing, and carried formidable punching power; he is often regarded as one of the hardest-punching light-welterweights in the division's history, and one of the greatest light-welterweights of all time.
As an amateur, Tszyu represented the Soviet Union, winning a bronze medal in the lightweight division at the 1989 World Championships, and gold in the light-welterweight division at the 1991 World Championships. He also won consecutive gold medals at the 1989 and 1991 European Championships.
BoxRec-style profile
- Birth name: Konstantin Borisovich Tszyu
- Born: September 19, 1969 — Serov, Russian SFSR, Soviet Union
- Nationality: Australian / Soviet
- Height: 5 ft 7 in (170 cm)
- Reach: 67 in (170 cm)
- Stance: Orthodox
- Pro debut: 1 Mar 1992 (Win by TKO vs Darrell Hiles)
- Last bout: 4 Jun 2005 (Loss by RTD vs Ricky Hatton)
- Total rounds boxed: 202 (summed from the bout table below)
- Divisions: Light-welterweight
- KO percentage: 80.6% (25 KO wins in 31 wins)
- Titles held (major, with reign dates): IBF light-welterweight title (first reign) January 28, 1995 – May 31, 1997 (won from Jake Rodríguez; four defenses, plus a no-contest title bout against Leonardo Mas; lost to Vince Phillips); WBC light-welterweight title August 21, 1999 – 2004 (won the interim title from Diosbelys Hurtado on November 28, 1998 and the vacant full title from Miguel Angel Gonzalez; defended against Ahmed Santos and Julio César Chávez; added the WBA (Super) title on February 3, 2001 against Sharmba Mitchell and the IBF title on November 3, 2001 against Zab Judah, then defended the unified titles against Ben Tackie and Jesse James Leija; by the November 6, 2004 Mitchell rematch only the IBF and The Ring titles were at stake, per the bout table); IBF and The Ring light-welterweight titles – June 4, 2005 (defended against Sharmba Mitchell; lost to Ricky Hatton in his final bout) — all dates per the bout table
Record at a glance
- Total bouts: 34
- Wins: 31
- Wins by KO: 25
- Losses: 2
- Losses by KO: 2
- Draws: 0
- No contests: 1
- Born: September 19, 1969 — Serov, Russian SFSR, Soviet Union
- Nationality: Australian / Soviet
- Height: 5 ft 7 in (170 cm)
- Reach: 67 in (170 cm)
- Stance: Orthodox
- Divisions: Light-welterweight
Fight-by-fight record
| No. | Date | Opponent | Result | Method | Round/Time | Venue / Notes |
|---|---|---|---|---|---|---|
| 1 | 1 Mar 1992 | Darrell Hiles | Win | TKO | 1 (8), 1:10 | Princes Park, Melbourne, Australia |
| 2 | 2 Apr 1992 | Nedrick Simmons | Win | KO | 1 (8), 1:58 | Sydney, Australia |
| 3 | 7 May 1992 | Tony Jones | Win | TKO | 2 (10), 0:15 | Convention and Exhibition Centre, Sydney, Australia |
| 4 | 23 Jul 1992 | Juan Laporte | Win | UD | 10 | Convention and Exhibition Centre, Sydney, Australia |
| 5 | 11 Sep 1992 | Daniel Ricardo Cusato | Win | TKO | 7 (10) | Sydney, Australia |
| 6 | 13 Nov 1992 | Sammy Fuentes | Win | TKO | 1 (10), 0:54 | Festival Hall, Melbourne, Australia |
| 7 | 30 Jan 1993 | Steve Larrimore | Win | TKO | 2 (10), 1:56 | The Pyramid, Memphis, Tennessee, US |
| 8 | 14 May 1993 | Larry LaCoursiere | Win | TKO | 1 (10) | Entertainment Centre, Newcastle, Australia |
| 9 | 18 Jun 1993 | Robert Rivera | Win | KO | 1 (10), 1:27 | Entertainment Centre, Newcastle, Australia |
| 10 | 23 Aug 1993 | Livingstone Bramble | Win | UD | 10 | Newcastle, Australia |
| 11 | 11 Jan 1994 | Hector Lopez | Win | UD | 10 | Hyatt Regency, Tampa, Florida, US |
| 12 | 2 May 1994 | Angel Hernandez | Win | RTD | 7 (10), 3:00 | Entertainment Centre, Newcastle, Australia |
| 13 | 29 Aug 1994 | Pedro Sanchez | Win | TKO | 4 (10) | Flinders Park, Melbourne, Australia |
| 14 | 28 Jan 1995 | Jake Rodríguez | Win | TKO | 6 (12), 1:50 | MGM Grand Garden Arena, Paradise, Nevada, US — ★ Title fight — Won IBF light-welterweight title |
| 15 | 25 Jun 1995 | Roger Mayweather | Win | UD | 12 | Entertainment Centre, Newcastle, Australia — ★ Title fight — Retained IBF light-welterweight title |
| 16 | 20 Jan 1996 | Hugo Pineda | Win | TKO | 11 (12), 2:38 | Parramatta Stadium, Sydney, Australia — ★ Title fight — Retained IBF light-welterweight title |
| 17 | 24 May 1996 | Corey Johnson | Win | KO | 4 (12), 1:21 | Entertainment Centre, Sydney, Australia — ★ Title fight — Retained IBF light-welterweight title |
| 18 | 14 Sep 1996 | Jan Piet Bergman | Win | KO | 6 (12), 1:23 | Entertainment Centre, Newcastle, Australia — ★ Title fight — Retained IBF light-welterweight title |
| 19 | 18 Jan 1997 | Leonardo Mas | NC | TD | 1 (12), 3:00 | Thomas & Mack Center, Paradise, Nevada, US — ★ Title fight — IBF light-welterweight title at stake; Originally a TD after Mas sustained a fractured jaw from an accidental foul, later ruled an NC |
| 20 | 31 May 1997 | Vince Phillips | Loss | TKO | 10 (12), 1:22 | Etess Arena, Atlantic City, New Jersey, US — ★ Title fight — Lost IBF light-welterweight title |
| 21 | 6 Dec 1997 | Ismael Armando Chaves | Win | TKO | 3 (12), 2:20 | Stockland Stadium, Townsville, Australia |
| 22 | 5 Apr 1998 | Calvin Grove | Win | KO | 1 (10), 2:59 | Entertainment Centre, Newcastle, Australia |
| 23 | 15 Aug 1998 | Rafael Ruelas | Win | TKO | 9 (12), 0:21 | County Coliseum, El Paso, Texas, US |
| 24 | 28 Nov 1998 | Diosbelys Hurtado | Win | TKO | 5 (12), 2:35 | Fantasy Springs Resort Casino, Indio, California, US — ★ Title fight — Won WBC interim light-welterweight title |
| 25 | 21 Aug 1999 | Miguel Angel Gonzalez | Win | TKO | 10 (12), 0:48 | Miccosukee Resort & Gaming, Miami, Florida, US — ★ Title fight — Won vacant WBC light-welterweight title |
| 26 | 12 Feb 2000 | Ahmed Santos | Win | TKO | 8 (12), 0:36 | Mohegan Sun Arena, Montville, Connecticut, US — ★ Title fight — Retained WBC light-welterweight title |
| 27 | 29 Jul 2000 | Julio César Chávez | Win | TKO | 6 (12), 1:28 | Veteran's Memorial Coliseum, Phoenix, Arizona, US — ★ Title fight — Retained WBC light-welterweight title |
| 28 | 3 Feb 2001 | Sharmba Mitchell | Win | RTD | 7 (12), 3:00 | Mandalay Bay Events Center, Paradise, Nevada, US — ★ Title fight — Retained WBC light-welterweight title; Won WBA (Super) light-welterweight title |
| 29 | 23 Jun 2001 | Oktay Urkal | Win | UD | 12 | Mohegan Sun Arena, Montville, Connecticut, US — ★ Title fight — Retained WBA (Super) and WBC light-welterweight titles |
| 30 | 3 Nov 2001 | Zab Judah | Win | TKO | 2 (12), 2:59 | MGM Grand Garden Arena, Paradise, Nevada, US — ★ Title fight — Retained WBA (Super) and WBC light-welterweight titles; Won IBF light-welterweight title |
| 31 | 18 May 2002 | Ben Tackie | Win | UD | 12 | Mandalay Bay Events Center, Paradise, Nevada, US — ★ Title fight — Retained WBA (Super), WBC, IBF, and The Ring light-welterweight titles |
| 32 | 19 Jan 2003 | Jesse James Leija | Win | RTD | 6 (12), 3:00 | Telstra Dome, Melbourne, Australia — ★ Title fight — Retained WBA (Unified), WBC, IBF, and The Ring light-welterweight titles |
| 33 | 6 Nov 2004 | Sharmba Mitchell | Win | TKO | 3 (12), 2:48 | Glendale Arena, Phoenix, Arizona, US — ★ Title fight — Retained IBF and The Ring light-welterweight titles |
| 34 | 4 Jun 2005 | Ricky Hatton | Loss | RTD | 11 (12), 3:00 | MEN Arena, Manchester, England — ★ Title fight — Lost IBF and The Ring light-welterweight titles |
Titles & notes
Major title reigns (start–end): IBF light-welterweight title (first reign) January 28, 1995 – May 31, 1997 (won from Jake Rodríguez; four defenses, plus a no-contest title bout against Leonardo Mas; lost to Vince Phillips); WBC light-welterweight title August 21, 1999 – 2004 (won the interim title from Diosbelys Hurtado on November 28, 1998 and the vacant full title from Miguel Angel Gonzalez; defended against Ahmed Santos and Julio César Chávez; added the WBA (Super) title on February 3, 2001 against Sharmba Mitchell and the IBF title on November 3, 2001 against Zab Judah, then defended the unified titles against Ben Tackie and Jesse James Leija; by the November 6, 2004 Mitchell rematch only the IBF and The Ring titles were at stake, per the bout table); IBF and The Ring light-welterweight titles – June 4, 2005 (defended against Sharmba Mitchell; lost to Ricky Hatton in his final bout) — all dates per the bout table
- 28 Jan 1995 vs Jake Rodríguez: Won IBF light-welterweight title
- 25 Jun 1995 vs Roger Mayweather: Retained IBF light-welterweight title
- 20 Jan 1996 vs Hugo Pineda: Retained IBF light-welterweight title
- 24 May 1996 vs Corey Johnson: Retained IBF light-welterweight title
- 14 Sep 1996 vs Jan Piet Bergman: Retained IBF light-welterweight title
- 18 Jan 1997 vs Leonardo Mas: IBF light-welterweight title at stake; Originally a TD after Mas sustained a fractured jaw from an accidental foul, later ruled an NC
- 31 May 1997 vs Vince Phillips: Lost IBF light-welterweight title
- 28 Nov 1998 vs Diosbelys Hurtado: Won WBC interim light-welterweight title
- 21 Aug 1999 vs Miguel Angel Gonzalez: Won vacant WBC light-welterweight title
- 12 Feb 2000 vs Ahmed Santos: Retained WBC light-welterweight title
- 29 Jul 2000 vs Julio César Chávez: Retained WBC light-welterweight title
- 3 Feb 2001 vs Sharmba Mitchell: Retained WBC light-welterweight title; Won WBA (Super) light-welterweight title
- 23 Jun 2001 vs Oktay Urkal: Retained WBA (Super) and WBC light-welterweight titles
- 3 Nov 2001 vs Zab Judah: Retained WBA (Super) and WBC light-welterweight titles; Won IBF light-welterweight title
- 18 May 2002 vs Ben Tackie: Retained WBA (Super), WBC, IBF, and The Ring light-welterweight titles
- 19 Jan 2003 vs Jesse James Leija: Retained WBA (Unified), WBC, IBF, and The Ring light-welterweight titles
- 6 Nov 2004 vs Sharmba Mitchell: Retained IBF and The Ring light-welterweight titles
- 4 Jun 2005 vs Ricky Hatton: Lost IBF and The Ring light-welterweight titles
Photo: Wikimedia Commons (). Featured image: https://upload.wikimedia.org/wikipedia/commons/b/b6/Kostya_Tszyu_2008.jpg?utm_source=en.wikipedia.org&utm_campaign=api&utm_content=original
Record source: Wikipedia professional boxing record table (cross-checked against the bout list), retrieved 2026-11-01.
