The challenge is that all those analyses of Ange's Celtic system have 2 wingers staying wide, a CF buzzing around the box, 2 x 8s bombing forwards constantly, and 2 inverted FBs, providing some solididity in the centre.
Neither Porro or Udogie are natural inverted FBs. Their strength is getting forwards & joining in with the attack. For me, Ange has to allow them to do this, or he's wasting their skillset.
Emerson rescued his Spurs career by proving himself a good defensive FB, so he could certainly help form a defensive 3 allowing Udogie to bomb forward on the other flank.
Same principle with Porro getting forward on the right ,and Davies or VDV2 helping to bolster the defence.
We shall see. Perhaps one of the reasons we're rumoured to be in for Kessie is that Ange has decided the solution to the conundrum is to have at least one of the 8s being what
bus-conductor
would call a "busy c***".. as well as a mobile, disciplined 6.
I may well be wrong.
But I think we'll ship a load of goals if we regularly start both Porro & Udogie in the same back 4 with licence to get forward at all times.