Hernan Gumy defeated Carlos Zwetsch 7-6 6-3 in the Brazil 2 Masters 2 round of 32 on clay. The upset overturned the form book — Carlos Zwetsch came in leading the head-to-head 1–0, but Hernan Gumy had been the form player, winning 3 of their last 8 on clay. Hernan Gumy claimed a first win over Carlos Zwetsch in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1991-04-15 | Brazil 2 Masters 4 | R16 | clay | Carlos Zwetsch | 7-6 6-3 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.