Martin Vassallo Arguello defeated Andres Schneiter 6-1 6-2 in the Argentina F3 round of 32 on clay. The upset overturned the form book — Andres Schneiter came in leading the head-to-head 1–0. Martin Vassallo Arguello claimed a first win over Andres Schneiter in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-05-03 | Argentina F3 | R32 | clay | Andres Schneiter | 6-1 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.