Mark Nielsen defeated Naoki Arimoto 6-2 6-3 in the Japan 1 Masters 2 round of 32 on hard. The result followed the form book — Mark Nielsen came in leading the head-to-head 2–0. Mark Nielsen extended the head-to-head to 3–0.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2003-09-01 | Japan F6 | R16 | hard | Mark Nielsen | 6-4 7-5 |
| 1999-06-07 | Japan 1 Masters 1 | R16 | hard | Mark Nielsen | 6-4 6-2 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.