Sachie Ishizu defeated Natsumi Hamamura 6-4 2-6 6-3 in the Niigata 25K round of 16 on hard. Sachie Ishizu extended the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2011-05-09 | Kurume 50K | R32 | grass | Sachie Ishizu | 6-2 6-2 |
| 2009-09-28 | Hamanako 25K | QF | carpet | Natsumi Hamamura | 7-5 3-6 6-0 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.