Sjeng Schalken defeated Daniel Vacek 6-3 6-3 1-6 6-3 in the Roland Garros round of 128 on clay. The upset overturned the form book — Daniel Vacek came in leading the head-to-head 2–1, defending last year's round of 64. Sjeng Schalken narrowed the head-to-head to 2–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-01-11 | Auckland | R16 | hard | Sjeng Schalken | 6-4 6-4 |
| 1998-08-03 | Canada Masters | R64 | hard | Daniel Vacek | 4-6 6-3 6-4 |
| 1998-05-25 | Roland Garros | R128 | clay | Daniel Vacek | 1-6 6-2 6-4 7-5 |
Averages over each player's completed matches in the selected window (200 vs 180). ATP, WTA & Challenger.
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About