Tasuku Iwami defeated Mark Nielsen 6-4 6-2 in the Japan F6 qualifying round on hard. The upset overturned the form book — Mark Nielsen came in leading the head-to-head 4–1. Tasuku Iwami narrowed the head-to-head to 4–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2005-09-05 | Japan F10 | F | hard | Mark Nielsen | 6-3 7-6(6) |
| 2004-04-12 | Japan F1 | QF | carpet | Mark Nielsen | 6-7(7) 6-2 6-2 |
| 2000-05-01 | China F2 | QF | hard | Mark Nielsen | 6-3 7-5 |
| 1999-10-25 | Japan F6 | QF | carpet | Mark Nielsen | 6-4 6-1 |
| 1998-03-25 | Japan F2 | R32 | carpet | Tasuku Iwami | 6-7 7-5 6-2 |
Averages over each player's completed matches in the selected window (4 vs 4). 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