Men's 400m Round 1 - Heat 3
dimanche 1 août 2021, 02h01 GMT – 07h01 GMT
| Nom | Temps | |
|---|---|---|
| 1 |  Michael Cherry | 44.82″ |
| 2 |  Jonathan Jones | + 0.22″ |
| 3 |  Christopher Taylor | + 0.38″ |
| 4 |  Dwight St. Hillaire | + 0.59″ |
| 5 | Luka Janezic | + 0.62″ |
| 6 | Gilles anthony Afoumba | + 1.21″ |
| 7 |  Lucas Carvalho | + 1.3″ |
| 8 | Mohammad jahir Rayhan | + 3.47″ |