Jeff Williams defeated Konstantin Don Gruber 6-4 6-4 in the Mexico 1 3 round of 32 on clay. The upset overturned the form book — Konstantin Don Gruber came in leading the head-to-head 1–0. Jeff Williams claimed a first win over Konstantin Don Gruber in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2001-03-12 | Mexico 1 4 | R16 | clay | Konstantin Don Gruber | 6-1 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.