Hiromasa Oku defeated Takuto Niki 6-2 6-3 in the Japan F6 round of 32 on clay. The upset overturned the form book — Takuto Niki came in leading the head-to-head 3–0. Hiromasa Oku claimed a first win over Takuto Niki in four meetings, narrowing the head-to-head to 3–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2014-03-17 | Japan F2 | R32 | hard | Takuto Niki | 7-6(5) 6-3 |
| 2012-06-11 | Japan F5 | QF | clay | Takuto Niki | 6-2 6-3 |
| 2011-06-06 | Japan F5 | R16 | clay | Takuto Niki | 1-6 6-2 6-0 |
Averages over each player's completed matches in the selected window (18 vs 181). 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