Alexander Donski defeated Benjamin Lock 6-3 6-7 6-4 in the M15 Pretoria 1 semi-final on hard. The upset overturned the form book — Benjamin Lock came in leading the head-to-head 1–0. Alexander Donski claimed a first win over Benjamin Lock in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2019-09-29 | M15 Johannesburg 1 | F | hard | Benjamin Lock | 6-7(5) 6-3 7-6(3) |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.