Didn’t he play with Mustafi-Kos-Holding at least once last season? I don’t think he necessarily prefers that there be one of Monreal/Kolasinac there, it’s just worked out that way through suspension and unavailability.
Not sure which is our best back 3 between Mustafi-Kos-Monreal and Mustafi-Kos-Holding, or even Holding-Kos-Monreal. Monreal is probably our best organiser back there so my feeling is it’s probably the first or maybe the third of those options, unless Mustafi improves in this respect.
Couldn’t really say with much authority though, tbh, having not seen many matches down the stretch last season. Would be interested in what other people think is our best back 3.