Gengo Kikuchi defeated Ryota Tanuma 6-4 6-2 in the Vietnam F2 qualifying round on hard. The upset overturned the form book — Ryota Tanuma came in leading the head-to-head 1–0, but Gengo Kikuchi had been the form player, winning 4 of their last 4 on hard. Gengo Kikuchi claimed a first win over Ryota Tanuma in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2015-03-23 | Japan F3 | R32 | hard | Ryota Tanuma | 6-3 7-5 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.