By surface
| Surface | Kei Nishikori | Ivo Karlovic |
|---|---|---|
| Hard | 3 | 2 |
All meetings (5)
| Date | Tour | Tournament | Round | Surface | Winner | Set 1 | Set 2 | Set 3 | Set 4 | Set 5 |
|---|---|---|---|---|---|---|---|---|---|---|
| 2019-01-14 | ATP | Australian Open | Round of 64 | Hard | Kei Nishikori | 6-3 | 7-66 | 5-7 | 5-7 | 7-67 |
| 2016-08-29 | ATP | US Open | Round of 16 | Hard | Kei Nishikori | 6-3 | 6-4 | 7-64 | ||
| 2014-02-10 | ATP | Memphis | Final | Hard | Kei Nishikori | 6-4 | 7-60 | |||
| 2013-02-25 | ATP | Delray Beach | Round of 32 | Hard | Ivo Karlovic | 4-5 | ||||
| 2012-02-10 | ATP | Davis Cup WG R1: JPN vs CRO | Round Robin | Hard | Ivo Karlovic | 4-6 | 4-6 | 3-6 |