Dominic Thiem defeated Kei Nishikori 6-1 6-4 in the Tour Finals round robin on hard. The upset overturned the form book — Kei Nishikori came in leading the head-to-head 3–1. Dominic Thiem narrowed the head-to-head to 3–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2018-10-22 | Vienna | QF | hard | Kei Nishikori | 6-3 6-1 |
| 2018-05-28 | Roland Garros | R16 | clay | Dominic Thiem | 6-2 6-0 5-7 6-4 |
| 2016-05-09 | Rome Masters | QF | clay | Kei Nishikori | 6-3 7-5 |
| 2015-06-15 | Halle | R32 | grass | Kei Nishikori | 7-6(4) 7-5 |
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About
Averages over each player's completed matches in the selected window (200 vs 200). ATP, WTA & Challenger.
Performance in the biggest moments — break points, deciding sets and tiebreaks (0–100, higher is better). About