| Final | time |   | L |  | 1. Jereem Richards |   Trinidad Tobago | 45.00 | CR NR | 6 |  | 2. Trevor Bassitt |   United States | 45.05 | PB | 4 |  | 3. Carl Bengtström |   Sweden | 45.33 | NR | 5 |  | 4. Benjamin Lobo Vedel |   Denmark | 45.67 | NR | 3 |  | 5. Patrik Šorm |   Czechia | 46.81 |   | 2 |  | 6. Marqueze Washington |   United States | 46.85 |   | 1 |   
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| Venue: Štark Arena, Cap.: 18,386. Final Sat 19.03.22 --:--. |   
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|   |  | 2 Heats with 12 Athletes. First 3 from each Heat advanced to Final. |   
| Ranking | time |   | H | L  |  | 1. Carl Bengtström |   Sweden | 45.92s | Q | 2 | 6 |  | 2. Jereem Richards |   Trinidad Tobago | 46.15s | Q | 1 | 4 |  | 3. Trevor Bassitt |   United States | 46.26s | Q | 2 | 4 |  | 4. Benjamin Lobo Vedel |   Denmark | 46.30s | Q | 1 | 3 |  | 5. Marqueze Washington |   United States | 46.36s | Q | 1 | 5 |  | 6. Julien Watrin |   Belgium | 46.54s |   | 1 | 6 |  | 7. Patrik Šorm |   Czechia | 46.55s | Q | 2 | 5 |  | 8. Bruno Hortelano |   Spain | 46.76s |   | 2 | 1 |  | 9. Mikhail Litvin |   Kazakhstan | 46.89s |   | 1 | 2 |  | 10.Boško Kijanović |   Serbia | 46.97s |   | 2 | 2 |  | 11.Kajetan Duszyński |   Poland | 47.21s |   | 1 | 1 |  | -. Christopher Taylor |   Jamaica | DNFs |   | 2 | 3 |   
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 |   |  | 5 Heats with 25 Athletes. First 2 from each Heat and Best 2 times advanced to Semi-Finals. |   
| Ranking | time |   | H | L  |  | 1. Julien Watrin |   Belgium | 45.88s | Q, NR | 1 | 6 |  | 2. Carl Bengtström |   Sweden | 46.45s | Q | 5 | 6 |  | 3. Trevor Bassitt |   United States | 46.47s | Q | 1 | 5 |  | 4. Christopher Taylor |   Jamaica | 46.48s | Q | 5 | 4 |  | 5. Bruno Hortelano |   Spain | 46.49s | q | 5 | 5 |  | 6. Patrik Šorm |   Czechia | 46.49s | Q | 3 | 5 |  | 7. Benjamin Lobo Vedel |   Denmark | 46.58s | Q | 3 | 6 |  | 8. Marqueze Washington |   United States | 46.66s | Q | 4 | 5 |  | 9. Jereem Richards |   Trinidad Tobago | 46.69s | Q | 2 | 5 |  | 10.Mikhail Litvin |   Kazakhstan | 46.72s | Q | 2 | 4 |  | 11.Kajetan Duszyński |   Poland | 46.75s | q | 1 | 3 |  | 12.Patrick Schneider |   Germany | 46.76s |   | 3 | 4 |  | 13.Tom Willems |   Australia | 46.77s |   | 3 | 3 |  | 14.Boško Kijanović |   Serbia | 46.88s | Q | 4 | 4 |  | 15.Zakithi Nene |   South Africa | 46.92s |   | 2 | 3 |  | 16.Håvard Bentdal Ingvaldsen |   Norway | 46.95s |   | 5 | 3 |  | 17.Isayah Boers |   Netherlands | 47.07s |   | 1 | 4 |  | 18.Pavel Maslák |   Czechia | 47.31s |   | 4 | 3 |  | 19.Mazen Al-Yassin |   Saudi Arabia | 47.65s |   | 1 | 2 |  | 20.Manuel Guijarro |   Spain | 47.74s |   | 2 | 6 |  | 21.Jovan Stojoski |   North Macedonia | 47.80s |   | 4 | 2 |  | 22.Pau Blasi |   Andorra | 49.82s |   | 2 | 2 |  | 23.Quentin Petit |   Comoros | 51.55s | SB | 3 | 2 |  | 24.Malique Smith |   US Virgin Islands | 51.98s | SB | 5 | 2 |  | -. Lucas Carvalho |   Brazil |  DQ TR17.4.3 | 4 | 6 |   
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