Mike Mather defeated Miguel Gallardo Valles 6-0 6-2 in the Mexico F1 semi-final on hard. The upset overturned the form book — Miguel Gallardo Valles came in leading the head-to-head 1–0. Mike Mather claimed a first win over Miguel Gallardo Valles in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-05-31 | Mexico F2 | R16 | hard | Miguel Gallardo Valles | 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.