| Argentina (2) |
|---|
| Mayer, Leonardo | | Pella, Guido |
| | Australien (1) |
|---|
| Tomic, Bernard |
| | | Brasilien (1) |
|---|
| Monteiro, Thiago |
|
| Canada (1) |
|---|
| Pospisil, Vasek |
| | | Kroatien (2) |
|---|
| Coric, Borna | | Pavic, Mate |
| | Cypern (1) |
|---|
| Baghdatis, Marcos |
|
| Georgien (1) |
|---|
| Basilashvili, Nikoloz |
| | Tyskland (2) |
|---|
| Gojowczyk, Peter | | Struff, Jan-Lennard |
| | Grækenland (1) |
|---|
| Tsitsipas, Stefano |
| |
| Rusland (2) |
|---|
| Khachanov, Karen | | Rublev, Andrey |
| | Serbien (2) |
|---|
| Lajovic, Dusan | | Troicki, Viktor |
| | Spanien (2) |
|---|
| Menendez-Maceiras, Adrian | | Ramos-Vinolas, Albert |
| |
| | Storbritannien (1) |
|---|
| Edmund, Kyle |
| | USA (2) |
|---|
| Donaldson, Jared | | Fritz, Taylor |
| | Usbekistan (1) |
|---|
| Istomin, Denis |
|