Matias Oneille defeated Andres Dellatorre 6-4 6-2 in the Argentina 4 round of 32 on clay. The upset overturned the form book — Andres Dellatorre came in leading the head-to-head 2–0. Matias Oneille claimed a first win over Andres Dellatorre in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2003-08-25 | Argentina F2 | QF | clay | Andres Dellatorre | 7-6(3) 3-6 6-1 |
| 2001-09-10 | Argentina F11 | R16 | clay | Andres Dellatorre | 7-5 6-4 |