In the return leg they battered Liverpool for 40 minutes. What do they have to show for it? 1 goal. You mean to tell me that if Messi and Griezmann would be in that line-up upfront, they would still have only one goal? Hell, Messi alone improves them beyond what they dream. Anyway, we went out to Roma ffs. Is that better than City going out to Liverpool? I mean, this argument would work if we'd have such a strong midfield and team.
The mid is not even the problem with that team even though they still don't have a Busi. They're going for Jorginho for a reason. They have inconsistent strikers and wingers. For as much as Sterling progressed this year, he still wastes sitters for fun. In important matches to boot. Sane is not a complete winger yet. Aguero and Jesus are hot and cold. Put Messi and Griezmann in front of that midfield and they would improve their chances in CL tenfold.
Ok, enough about City. Like MTL_Barca said, Thiago is far from a liability in defence. Dude is one of the smartest players when it comes to reading the game. Makes a good amount of interceptions by positioning himself properly akin to Xavi and Busi.
Even if you argue that we will be vulnerable, it's not like we are such a defensive force with Rakitic and Busi, that disrupting this partnership spells trouble. You have to look at what we have now before we turn our noses away at running such a line-up.
Maybe Thiago, who is injury prone, is not the solution, but we certainly have to change something in our midfield. Either players or tactics. Probably both. We can't continue this way, that much is for sure.