Konstantin Don Gruber defeated Alejandro Vargas Aboy 6-0 6-2 in the Switzerland 2 3 qualifying round on clay. The upset overturned the form book — Alejandro Vargas Aboy came in leading the head-to-head 1–0. Konstantin Don Gruber claimed a first win over Alejandro Vargas Aboy in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2003-06-16 | Slovenia F3 | QF | clay | Alejandro Vargas Aboy | 6-7(0) 6-4 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.