Indeed but if our defenders are s***, why play a system that relies on using three of them and them all being extremely positionally disciplined? It would surely be better to play an additional midfielder and try to control the game enough to relieve pressure on the defence.
In defence we are picking three from Disasi, Richards, Lerma, Ahanor, Canvot, Tomiyasu
In midfield we are picking two from Wharton, Timber, Hughes, Kamada, Lerma, Doucoure.
I would say that second pool of players is significantly stronger.