This Is Anfield understands that the Spaniard has not been included in the Reds’ selection for the first part of the competition.
But that is not the case in Europe, where both are only eligible to feature alongside other foreign stars on ‘List A’.
That left Klopp with 18 players and only 17 spots in which to register them, and it is Adrian who has been forced to miss out as a result.
However, his omission is also understood to be down to the presence of a UEFA loophole that could still see him feature in some capacity.
The rules state that, in the case of any named goalkeepers being struck down by long-term injury or illness, a replacement can be called upon.