Guillermo Rivera Aranguiz defeated Mauricio Doria Medina 6-4 6-3 in the Chile F3 qualifying round on clay. The upset overturned the form book — Mauricio Doria Medina came in leading the head-to-head 1–0. Guillermo Rivera Aranguiz claimed a first win over Mauricio Doria Medina in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2008-09-15 | Bolivia F2 | QF | clay | Mauricio Doria Medina | 7-6(4) 6-7(1) 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.