Rafael Serpa Guinazu defeated Federico Dondo 2-6 6-2 6-0 in the Argentina B Masters 1 round of 16 on clay. The upset overturned the form book — Federico Dondo came in leading the head-to-head 1–0. Rafael Serpa Guinazu claimed a first win over Federico Dondo in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1997-11-01 | Uruguay Masters 2 | R32 | clay | Federico Dondo | 6-4 6-0 |