1998–99 Athletic Bilbao season

Athletic had finished second the previous season, and though they gathered only five points fewer - all from losing instead of drawing games - this was enough to drag them down to 8th place.

The club had applied and qualified for the Intertoto Cup, but in the end declined to enter the competition.

Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Players may hold more than one non-FIFA nationality.