The veteran left-back picked up a foot problem against Dynamo Kiev in the Champions League in midweek and was not able to complete a full training session on Friday, but Koeman is still confident that he will be able to play some part.
Martin Braithwaite, Pedri and Ronald Araujo also continue their spells out of action, while Ousmane Dembele has reportedly flown to Finland for an assessment of his injury and will not make the cut either.
Alba's possible absence could see 18-year-old Alex Balde given the nod at left-back, while Eric Garcia should return to the heart of defence in place of Clement Lenglet after serving a European ban in midweek.
Ronald Koeman left Ansu Fati out of the starting lineup for the win over Dynamo Kiev, so the 18-year-old should certainly return to the first XI alongside Memphis Depay and Sergino Dest as Luuk de Jong makes way.
Barcelona possible starting lineup: Ter Stegen; Roberto, Pique, Garcia, Balde; Gavi, Busquets, De Jong; Dest, Depay, Fati
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