Carlos Zwetsch defeated Hernan Gumy 7-6 6-3 in the Brazil 2 Masters 4 round of 16 on clay. The upset overturned the form book — Hernan Gumy came in leading the head-to-head 1–0. Carlos Zwetsch claimed a first win over Hernan Gumy in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1991-04-15 | Brazil 2 Masters 2 | R32 | clay | Hernan Gumy | 7-6 6-3 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.