Reto Staubli defeated Paul Dogger 5-7 6-3 7-6 in the Czechoslovakia Masters 4 qualifying round on clay. The upset overturned the form book — Paul Dogger came in leading the head-to-head 1–0. Reto Staubli claimed a first win over Paul Dogger in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1991-08-26 | Czechoslovakia Masters 1 | R32 | clay | Paul Dogger | 6-3 6-1 |