Tatsuma Ito defeated Tasuku Iwami 6-3 3-6 6-4 in the Japan F1 semi-final on hard. The upset overturned the form book — Tasuku Iwami came in leading the head-to-head 2–1, but Tatsuma Ito had been the form player, winning 2 of their last 4 on hard. Tatsuma Ito narrowed the head-to-head to 2–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2008-06-16 | Japan F5 | R32 | carpet | Tasuku Iwami | 7-6(5) 6-4 |
| 2006-10-16 | Japan F11 | QF | hard | Tasuku Iwami | 6-2 7-6(3) |
| 2006-06-19 | Japan F7 | R32 | carpet | Tatsuma Ito | 4-1 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.