Marco Osorio defeated Armando Perez 6-3 3-6 6-1 in the Mexico 4 Masters 1 qualifying round on hard. The upset overturned the form book — Armando Perez came in leading the head-to-head 2–1. Marco Osorio narrowed the head-to-head to 2–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1998-02-07 | Cuba Mexico Masters 3 | R16 | hard | Armando Perez | 6-2 6-4 |
| 1995-09-30 | Mexico 4 Masters 3 | SF | hard | Armando Perez | 6-3 6-3 |
| 1995-04-22 | Mexico 2 Masters 2 | R32 | clay | Marco Osorio | 6-0 6-2 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.