Natalia Gussoni defeated Cecilia Guillenea 6-0 6-0 in the Buenos Aires 10K qualifying round on clay. The result followed the form book — Natalia Gussoni came in leading the head-to-head 3–0. Natalia Gussoni extended the head-to-head to 4–0.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-05-10 | Tortosa 10K | R32 | clay | Natalia Gussoni | 6-3 6-4 |
| 1998-09-15 | La Paz 10K | R32 | clay | Natalia Gussoni | 6-3 6-3 |
| 1998-08-31 | Guayaquil 10K | R16 | clay | Natalia Gussoni | 6-3 6-2 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.