Denis Istomin defeated Maximilian Marterer 6-3 6-3 in the Kitzbuhel quarter-final on clay. The upset overturned the form book — Maximilian Marterer came in leading the head-to-head 1–0, defending last year's round of 32. Denis Istomin claimed a first win over Maximilian Marterer in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2017-06-19 | Halle | Q1 | grass | Maximilian Marterer | 7-6(5) 7-6(3) |
Averages from each player's recent completed matches (20 vs 20). ATP, WTA & Challenger.