Unai Emery has a choice to make very soon, does he continue using defenders that have been a disappointment so far this season or does he go with a completely new back four against Manchester United on Monday evening.
Normally the manager has gone with a back four of Maitland-Niles, Kolasinac, Luiz and Sokratis, however, there is very good reasons not to use any of those players against the Red Devils.
Of course, Maitland-Niles is suspended so that make that decision very easy for Emery, Bellerin can just step in there. I also do not think you need to be Pep Guardiola to know that Kieran Tierney simply has to replace Kolasinac.
The tricky positions are the centre backs, does he stick with Sokratis and Luiz or drop just one of them or both?
I suspect most fans will argue that Rob Holding and Calum Chambers should be used as the centre back pairings. Chambers is in fantastic form right now and Holding showed last night how much he has been missed.
Emery may see it as a bit risky to go with a brand new back four against United and will probably want to retain Luiz for his experience but on form alone, I would have suggested Mustafi instead of the Brazilian if experience is the criteria.
It is going to be a huge call for Emery whatever way he goes because if he gets it wrong then he will be held solely responsible, unfairly or not.
The one huge positive now though, is that the boss finally has a full set of defenders to choose from and will not be forced to play anyone out of position or out of form.
It is now down to the Spaniard to make the right calls.