Juan Antonio Marin defeated Sebastian Prieto 7-6 7-6 in the Vina del Mar q16 on clay. The upset overturned the form book — Sebastian Prieto came in defending last year's round of 32. Juan Antonio Marin extended the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2004-04-12 | Valencia | Q32 | hard | Juan Antonio Marin | 7-5 4-6 6-3 |
| 2003-02-10 | Vina del Mar | Q32 | clay | Sebastian Prieto | 1-6 6-2 7-5 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.