Nickolai Dyachok defeated Sergei Yaroshenko 6-7 6-3 6-2 in the Bulgaria 4 round of 32 on clay. The upset overturned the form book — Sergei Yaroshenko came in leading the head-to-head 2–0. Nickolai Dyachok claimed a first win over Sergei Yaroshenko in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2006-03-06 | Poland F3 | R16 | hard | Sergei Yaroshenko | 6-3 7-5 |
| 2000-09-18 | Ukraine F1 | R32 | clay | Sergei Yaroshenko | 7-6(2) 6-1 |