Christopher Kas defeated Thiemo Maier 0-6 6-2 6-2 in the Italy 4 3 round of 16 on clay. The upset overturned the form book — Thiemo Maier came in leading the head-to-head 1–0, but Christopher Kas had been the form player, winning 3 of their last 6 on clay. Christopher Kas claimed a first win over Thiemo Maier in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-08-16 | Slovak Republic Masters 2 | R32 | clay | Thiemo Maier | 6-1 6-4 |