We didn't need to experiment because we knew he was coming back. I don't mean experimenting as in chucking random players in, I mean it more in terms of whether he'd consider a more drastic change to our structure and system to help us cope. With Rodri on the pitch we dominated Arsenal. He went off, they got a foothold. Against the best sides, he won't play Rico as a RB inverting, he'll play him in midfield if at all. Walker can't invert, and it leaves us potentially lacking in the midfield where Rodri otherwise just mops up everything and is the force that helps us unlock teams.
Without Foden and De Bruyne, and I mean Foden of last season, it's a harder job. I'd like to see Gvardiol inverting personally. I think he's the physical player we need there, whilst being excellent on the ball. But I think the issue there is Dias tends to be the choice at LCB and just couldn't cover the space the way Akanji can from RCB if someone inverts.