Pablo Minutella defeated Ruben Alvarenga 6-4 6-4 in the Bolivia Chile Masters 1 round of 32 on clay. The upset overturned the form book — Ruben Alvarenga came in leading the head-to-head 1–0, but Pablo Minutella had been the form player, winning 4 of their last 10 on clay. Pablo Minutella claimed a first win over Ruben Alvarenga in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1991-06-17 | Brazil 4 Masters 4 | R32 | clay | Ruben Alvarenga | 6-3 6-4 |