Dominique Graf defeated Rudolf Niklas Christiansen 6-3 6-3 in the M15 Heraklion 6 q16 on hard. The upset overturned the form book — Rudolf Niklas Christiansen came in leading the head-to-head 1–0. Dominique Graf claimed a first win over Rudolf Niklas Christiansen in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2025-08-19 | M25 Ueberlingen 1 | Q16 | clay | Rudolf Niklas Christiansen | 6-4 3-1 |