Federico Dondo defeated Martin Vassallo Arguello 2-6 6-3 7-6 in the Brazil F5 round of 16 on clay. The result followed the form book — Federico Dondo came in leading the head-to-head 2–1. Federico Dondo extended the head-to-head to 3–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-05-17 | Chile F2 | R32 | clay | Federico Dondo | 7-6 6-3 |
| 1999-05-10 | Chile F1 | R16 | clay | Federico Dondo | 6-3 3-6 6-4 |
| 1998-10-26 | Argentina F5 | R32 | clay | Martin Vassallo Arguello | 6-4 7-5 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.