| 1. Round | 04/03/2018 | Seattle Sounders | - | Los Angeles FC | 0:1 | ||||
| 1. Round | 18/03/2018 | FC Dallas | - | Seattle Sounders | 3:0 |  |
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| 2. Round | 30/04/2018 | Los Angeles FC | - | Seattle Sounders | 1:0 | ||||
| 3. Round | 26/05/2018 | Seattle Sounders | - | Real Salt Lake | 0:1 | ||||
| 4. Round | 03/06/2018 | Real Salt Lake | - | Seattle Sounders | 2:0 | ||||
| 5. Round | 08/07/2018 | New England Revolution | - | Seattle Sounders | 0:0 |
USA