The Athletic Club match was a big opportunity for Barcelona to cut into the lead of Real Madrid at the top of the table.
With Napoli gaining in form, having demolished Sassuolo 6-1, followed by a confidence-boosting 2-1 defeat of Juventus, the Catalan giants needed a big win themselves to keep the hope for silverware alive.
Instead, they dropped two points, and lost two of their most important players to injury.
Frenkie de Jong and Pedri will both be out for at least six weeks.
During that time, Barcelona will face challenges against Mallorca, who have made it to the Copa del Rey final, Napoli in the Champions League Round of 16, Atletico Madrid, and finally a Las Palmas side who has been one of the surprises of this La Liga season.