400m Men Heats, Heat:1 of 6 ; Official result since 14:39
David Gillick 45.52 (2007)
| Rank | Lane | ID | Name | PB | Team | Cat | Result | Info | Video |
| 1 | 6 | 132 | HARVEY Jason | 00:47.15 | Crusaders A.C. | 49.25 | q | ||
| 2 | 5 | 253 | MURPHY Adam | 00:48.80 | St. L. O'Toole A.C. | 50.13 | |||
| 3 | 2 | 322 | ST. CLARE JOHNSON Chris | 00:00.00 | Enniscorthy Juvenile A.C. | 51.25 | |||
| 4 | 3 | 211 | MCELGUNN Cathal | Carrick-On-Shannon A.C. | 52.43 | ||||
| 5 | 4 | 128 | HALPIN Adam | 54:00.00 | Donore Harriers | 56.02 |