| Lane | Athlete | Yr. | Team | Seed | Note |
|---|---|---|---|---|---|
| 1 | FLACK, Cory | 9 | DeSoto High School | 1:00.06 | Verified |
| 2 | DUEPNER, Tristan | SO | DeSoto High School | 58.70 | Verified |
| 3 | BOHNERT, Owen | JR | Perryville High School | 58.27 | Verified |
| 4 | WOOD, Zane | SO | Farmington High School | 56.25 | Verified |
| 5 | MOON, Brock | JR | Farmington High School | 57.89 | Verified |
| 6 | HOLMAN, Kevin | SO | Windsor (Imperial) High School | 58.29 | Verified |
| 7 | MOEHLENBROCK, Bailey | JR | Affton High School | 58.94 | Verified |
| Lane | Athlete | Yr. | Team | Seed | Note |
|---|---|---|---|---|---|
| 1 | BELCHER, Aidan | JR | Hillsboro High School | 56.08 | |
| 2 | SANDERS, Marcus | SO | Sikeston High School | 54.33 | Verified |
| 3 | LOVELACE, Josiah | JR | Affton High School | 52.07 | Verified |
| 4 | HOLLAND, Noah | SR | Hillsboro High School | 50.01 | Verified |
| 5 | BATES, Hunter | SO | Festus High School | 51.91 | Verified |
| 6 | GANTZ, DANIEL | SR | North County High School | 52.77 | Verified |
| 7 | REESE, Jackson | JR | Festus High School | 54.39 | Verified |
| 8 | ELLER, Mason | SO | Windsor (Imperial) High School | 56.18 | Verified |