Jack Gibbens defeated Karlo Cubelic 7-6 7-6 in the M25 Glasgow 2 q32 on hard. The upset overturned the form book — Karlo Cubelic came in leading the head-to-head 1–0. Jack Gibbens claimed a first win over Karlo Cubelic in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2021-03-29 | M15 Sharm El Sheikh 9 | Q32 | hard | Karlo Cubelic | 6-3 6-4 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.