Konstantin Don Gruber defeated Marko Neunteibl 7-6 6-4 in the Slovenia F3 qualifying round on clay. The upset overturned the form book — Marko Neunteibl came in leading the head-to-head 3–0. Konstantin Don Gruber claimed a first win over Marko Neunteibl in four meetings, narrowing the head-to-head to 3–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2003-09-08 | Slovak Rep F1 | F | clay | Marko Neunteibl | 7-5 1-6 7-5 |
| 2003-07-14 | Austria F2 | SF | clay | Marko Neunteibl | 6-2 7-6(0) |
| 2003-07-07 | Austria F1 | R32 | clay | Marko Neunteibl | 6-3 6-1 |