| date | Pair 1 | sets | Pair 2 | set 1 | set 2 | TB | dur (pts | 
| Wed 23.05.18 | Oliver Marach / Mate Pavic |  AUT |  CRO | 1 | 2-0 | Marco Cecchinato / Andreas Seppi |  ITA |  ITA |   | 6-0 | 6-2 |   | 0:36 (52-22) | 
| Mon 21.05.18 | Jonathan Erlich / Marton Fucsovics |  ISR |  HUN |   | 2-0 | Marius Copil / Constantin Sturdza |  ROU |  SUI | WC | 6-3 | 6-0 |   | 0:49 (51-32) | 
| Sun 20.05.18 | Antoine Bellier / Johan Nikles |  SUI |  SUI | WC | 2-1 | Max Mirnyi / Philipp Oswald |  BLR |  AUT | 3 | 3-6 | 6-1 | [10-5] | 0:54 (53-41) | 
| Tue 22.05.18 | Robert Lindstedt / Andrei Vasilevski |  SWE |  BLR |   | 2-0 | Andre Begemann / Antonio Sancic |  GER |  CRO |   | 7-64 | 7-69 |   | 1:45 (87-79) | 
| Sun 20.05.18 | Steve Johnson / Sam Querrey |  USA |  USA |   | 2-0 | Peter Gojowczyk / Andreas Haider-Maurer |  GER |  AUT | PR | 6-3 | 6-4 |   | 0:55 (57-45) | 
| Mon 21.05.18 | Dominic Inglot / Franko Skugor |  GBR |  CRO |   | 2-0 | Marcelo Demoliner / Santiago Gonzalez |  BRA |  MEX | 4 | 7-65 | 6-4 |   | 1:34 (66-66) | 
| Sun 19.05.18 | Scott Lipsky / David Marrero |  USA |  ESP |   | 2-1 | Wesley Koolhof / Artem Sitak |  NED |  NZL |   | 7-66 | 4-6 | [10-7] | 1:39 (76-78) | 
| Tue 22.05.18 | Ivan Dodig / Rajeev Ram |  CRO |  USA | 2 | 2-0 | Sander Arends / Adil Shamasdin |  NED |  CAN |   | 6-3 | 7-63 |   | 1:18 (71-58) |