Patricio Heras defeated Guillermo Bujniewicz 6-1 6-0 in the Argentina F15 qualifying round on clay. The upset overturned the form book — Guillermo Bujniewicz came in leading the head-to-head 1–0. Patricio Heras claimed a first win over Guillermo Bujniewicz in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2009-10-19 | Argentina F20 | R32 | clay | Guillermo Bujniewicz | 2-6 6-0 6-2 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.