Ku Keon Kang defeated Yusuke Watanuki 6-1 3-6 6-2 in the Korea F10 qualifying round on hard. The upset overturned the form book — Yusuke Watanuki came in leading the head-to-head 1–0, but Ku Keon Kang had been the form player, winning 3 of their last 5 on hard. Ku Keon Kang claimed a first win over Yusuke Watanuki in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2015-08-24 | Korea F5 | R32 | hard | Yusuke Watanuki | 6-1 6-1 |
Averages over each player's completed matches in the selected window (23 vs 52). 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