| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 1173 | Kerron Clement | 
                                         
                                        USA
                                     | 
                                    48.00 Q SB | 0.158 | 
| 2 | 329 | Felix Sánchez | 
                                         
                                        DOM
                                     | 
                                    48.34 Q SB | 0.154 | 
| 3 | 948 | Javier Culson | 
                                         
                                        PUR
                                     | 
                                    48.43 Q | 0.176 | 
| 4 | 671 | Danny McFarlane | 
                                         
                                        JAM
                                     | 
                                    48.49 q | 0.161 | 
| 5 | 1112 | Jehue Gordon | 
                                         
                                        TTO
                                     | 
                                    48.77 q | 0.162 | 
| 6 | 979 | L.J. van Zyl | 
                                         
                                        RSA
                                     | 
                                    48.80 | 0.168 | 
| 7 | 1163 | Andrés Silva | 
                                         
                                        URU
                                     | 
                                    49.34 NR | 0.143 | 
| 8 | 133 | Brendan Cole | 
                                         
                                        AUS
                                     | 
                                    49.92 | 0.186 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 1191 | Bershawn Jackson | 
                                         
                                        USA
                                     | 
                                    48.23 Q | 0.146 | 
| 2 | 509 | David GREENE | 
                                         
                                        GBR
                                     | 
                                    48.27 Q PB | 0.156 | 
| 3 | 583 | PeriklÃs Iakovákis | 
                                         
                                        GRE
                                     | 
                                    48.73 Q SB | 0.180 | 
| 4 | 673 | Isa Phillips | 
                                         
                                        JAM
                                     | 
                                    48.93 | 0.238 | 
| 5 | 294 | Omar Cisneros | 
                                         
                                        CUB
                                     | 
                                    49.21 | 0.189 | 
| 6 | 1176 | Johnny Dutch | 
                                         
                                        USA
                                     | 
                                    49.28 | 0.164 | 
| 7 | 131 | Tristan Thomas | 
                                         
                                        AUS
                                     | 
                                    49.76 | 0.160 | 
| 8 | 712 | Kazuaki Yoshida | 
                                         
                                        JPN
                                     | 
                                    50.34 | 0.175 |