Sebastian Decoud defeated Mariano Delfino 6-1 6-1 in the Uruguay F1 qualifying round on clay. The upset overturned the form book — Mariano Delfino came in leading the head-to-head 2–1, but Sebastian Decoud had been the form player, winning 6 of their last 10 on clay. Sebastian Decoud narrowed the head-to-head to 2–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2005-09-12 | Argentina F11 | R32 | clay | Sebastian Decoud | 6-4 1-1 |
| 2001-03-19 | Argentina F2 | QF | clay | Mariano Delfino | 7-6(3) 6-2 |
| 2000-03-27 | Argentina F3 | R32 | clay | Mariano Delfino | 6-1 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.