Guillaume Couillard defeated Guillaume Marx 7-5 7-5 in the France 4 Masters 1 semi-final on clay. The upset overturned the form book — Guillaume Marx came in leading the head-to-head 1–0. Guillaume Couillard claimed a first win over Guillaume Marx in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2000-04-10 | Italy 2 3 | SF | clay | Guillaume Marx | 7-5 6-1 |