Head to head
1
Hard
0
1
Carpet
0
Jan Siemerink's wins on the left · Mark Koevermans's on the right · bar lengths share one scale
All meetings (2)
| 1991 | Rotterdam | Carpet | R32 | Jan Siemerink | 3-6 6-4 6-2 |
| 1991 | Australian Open | Hard | R32 | Jan Siemerink | 4-6 6-2 6-4 3-6 6-1 |
Methodology
Head-to-head totals and surface splits exclude walkovers (no match was played), which follows ATP convention — walkover meetings still appear in the match list. The momentum chart plots the running lead across all counted meetings, oldest to newest.