| 1. Round | 29/08/1998 | Real Zaragoza | - | Athletic Club | 2:0 | ||||
| 2. Round | 11/09/1998 | Athletic Club | - | Racing Santander | 2:0 | ||||
| 3. Round | 19/09/1998 | CF Extremadura | - | Athletic Club | 0:1 | ||||
| 5. Round | 03/10/1998 | RC Celta | - | Athletic Club | 3:2 | ||||
| 33. Round | 08/05/1999 | Deportivo La Coruña | - | Athletic Club | 1:1 | ||||
| 34. Round | 15/05/1999 | Athletic Club | - | Villarreal CF | 2:0 | ||||
| 35. Round | 22/05/1999 | Real Valladolid | - | Athletic Club | 0:3 |  |
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| 36. Round | 28/05/1999 | Athletic Club | - | FC Barcelona | 1:3 | |
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| 37. Round | 12/06/1999 | Athletic Club | - | CD Alavés | 5:0 | |
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| 38. Round | 19/06/1999 | Real Betis | - | Athletic Club | 1:4 |
Spain