Nam Hoon Kim defeated Seong Kon Kim 7-5 6-2 in the Korea Masters 4 round of 16 on clay. The upset overturned the form book — Seong Kon Kim came in leading the head-to-head 1–0. Nam Hoon Kim claimed a first win over Seong Kon Kim in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1991-05-20 | Korea Masters 1 | SF | clay | Seong Kon Kim | 7-6 6-0 |