Alejandro Fabbri defeated Gustavo Marcaccio 6-3 6-3 in the El Salvador F1 qualifying round on clay. The upset overturned the form book — Gustavo Marcaccio came in leading the head-to-head 2–0. Alejandro Fabbri claimed a first win over Gustavo Marcaccio in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2003-04-21 | Chile F3 | R32 | clay | Gustavo Marcaccio | 4-6 6-1 7-6(6) |
| 2000-08-14 | Argentina F10 | R32 | clay | Gustavo Marcaccio | 6-1 6-1 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.