Jae Sung An defeated Harri Heliovaara 6-4 6-3 in the Korea F4 round of 16 on hard. The upset overturned the form book — Harri Heliovaara came in leading the head-to-head 1–0, but Jae Sung An had been the form player, winning 2 of their last 5 on hard. Jae Sung An claimed a first win over Harri Heliovaara in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2010-04-12 | Korea F2 | R16 | hard | Harri Heliovaara | 6-3 7-5 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.