Jun Kato advanced when Konstantin Don Gruber retired 5-7 6-3 2-0 in the New Zealand F2 qualifying round. Jun Kato 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 |
|---|---|---|---|---|---|
| 2003-02-24 | New Zealand F1 | R16 | hard | Konstantin Don Gruber | 4-6 6-3 6-3 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.