| Semifinal - 24.08.04 | | Heat 1 | Team | Time | | 1. Felix Sanchez | Dom | 47.93s | | 2. Marek Plawgo | Pol | 48.16s NR | | 3. Alwyn Myburgh | Rsa | 48.21s SB | | 4. Angelo Taylor | USA | 48.72s | | 5. Hadi Soua An Al Somaily | Sau | 48.98s SB | | 6. Mikhail Lipskiy | Rus | 49.10s | | 7. Edivaldo Monteiro | Por | 49.26s | | 8. Dean Griffiths | Jam | 49.51s | | Heat 2 | Team | Time | | 1. Danny McFarlane | Jam | 48.00s PB | | 2. Bennie Brazell | USA | 48.19s | | 3. Dai Tamesue | Jpn | 48.46s SB | | 4. Periklis Iakovakis | Gre | 48.47s SB | | 5. Llewellyn Herbert | Rsa | 48.57s | | 6. Eduardo Ivan Rodriguez | Spa | 49.77s | | 7. Stepan Tesarik | Cze | 49.87s | | 8. Christopher Rawlinson | Gbr | 50.89s | | Heat 3 | Team | Time | | 1. James Carter | USA | 48.18s | | 2. Bayano Kamani | Pan | 48.23s NR | | 3. Naman Keita | Fra | 48.24s | | 4. Kemel Thompson | Jam | 48.25s SB | | 5. Jiri Muzik | Cze | 48.88s | | 6. Ockert Cilliers | Rsa | 49.01s | | 7. Boris Gorban | Rus | 49.46s | | 8. Yevgeniy Meleshenko | Kaz | 49.48s |
| | Round 1 - 23.08.04 | | Heat 1 | Team | Time | | 1. Angelo Taylor | USA | 48.79s | | 2. Jiri Muzik | Cze | 48.85s SB | | 3. Christopher Rawlinson | Gbr | 48.94s | | 4. Boris Gorban | Rus | 49.25s | | 5. Yevgeniy Meleshenko | Kaz | 49.43s | | 6. Ken Yoshizawa | Jpn | 50.95s | | 7. Kurt Couto | Moz | 51.18s NR | | Heat 2 | Team | Time | | 1. Danny McFarlane | Jam | 48.35s SB | | 2. Bennie Brazell | USA | 48.57s | | 3. Marek Plawgo | Pol | 48.67s SB | | 4. Llewellyn Herbert | Rsa | 48.70s | | 5. Stepan Tesarik | Cze | 49.44s | | 6. Alaa Motar | Irq | 51.97s | | - Yacnier Luis | Cub | Disq | | Heat 3 | Team | Time | | 1. James Carter | USA | 48.64s | | 2. Periklis Iakovakis | Gre | 48.69s SB | | 3. Dai Tamesue | Jpn | 48.80s | | 4. Eduardo Ivan Rodriguez | Spa | 49.25s | | 5. Bayano Kamani | Pan | 49.37s | | 6. Ibrahima Maiga | Mli | 50.63s | | 7. Michael Aguilar | Blz | 51.21s | | Heat 4 | Team | Time | | 1. Felix Sanchez | Dom | 48.51s | | 2. Alwyn Myburgh | Rsa | 48.84s | | 3. Mikhail Lipskiy | Rus | 49.00s | | 4. Hadi Soua An Al Somaily | Sau | 49.15s SB | | 5. Dean Griffiths | Jam | 49.41s | | 6. Cedric El Idrissi | Swi | 49.44s | | 7. Mowen Boino | Png | 50.97s NR | | Heat 5 | Team | Time | | 1. Kemel Thompson | Jam | 48.66s SB | | 2. Naman Keita | Fra | 48.88s | | 3. Ockert Cilliers | Rsa | 49.12s | | 4. Edivaldo Monteiro | Por | 49.53s | | 5. Ibrahim Al Hamaidi | Sau | 49.64s | | 6. Matthew Douglas | Gbr | 49.77s | | 7. Ibrahim Tondi | Ngr | 52.62s |
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