I know what you are saying - and he looked miles out of his depth in the 15 mins he was there at old trafford in 2017. However.. I just trust the man/player more than Stones. Infact i'm at an impasse where I would barely consider stones a centre half himself; he is so frail. Can definitely picture ferna in a back 3/5 as the centre link with midfield and walker/otamendi *gags* beside him - cancelo and mendy either side of those..