Philipp Piyamongkol defeated Ralph Grambow 6-4 6-2 in the Germany 1 Satellite 3 round of 32 on carpet. The upset overturned the form book — Ralph Grambow came in leading the head-to-head 2–0. Philipp Piyamongkol claimed a first win over Ralph Grambow in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2006-03-06 | Canada F1 | R32 | hard | Ralph Grambow | 6-7(5) 6-3 6-3 |
| 2005-10-03 | Germany 1 Satellite 2 | R16 | carpet | Ralph Grambow | 7-6(6) 6-4 |