Diego Ayala defeated Jim Thomas 2-6 6-1 6-3 in the Indianapolis q16 on hard. The upset overturned the form book — Jim Thomas came in leading the head-to-head 1–0. Diego Ayala claimed a first win over Jim Thomas in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-03-26 | USA 1 Masters 3 | R64 | hard | Jim Thomas | 7-6 4-6 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.