Patricio Arquez defeated Matias Oneille 7-5 6-2 in the Argentina 1 Masters 4 round of 32 on clay. The upset overturned the form book — Matias Oneille came in leading the head-to-head 3–1. Patricio Arquez narrowed the head-to-head to 3–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2003-09-08 | Bolivia F1 | R32 | clay | Matias Oneille | 7-6(3) 2-6 7-6(3) |
| 2003-04-14 | Chile F2 | R32 | clay | Matias Oneille | 6-1 6-1 |
| 2000-09-04 | Peru F2 | QF | clay | Patricio Arquez | 6-3 6-2 |
| 1999-05-29 | Argentina 1 Masters 2 | QF | clay | Matias Oneille | 3-6 6-1 6-3 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.