Sissoko, Poulsen, Marchisio, Tiago, Zanetti, Ekdal.
At the moment we have 6 CMs fighting for 2 places. In reality it's 5 midfielders fighting for 2 places because Ekdal is not a candidate for the first team yet.
5 for 2 is more than enough and it's obvious that if we buy D'Agostino one of those 5 players will have to leave.
Since D'Agostino isn't a ball winner he can only replace on of the more creative players : Tiago or Zanetti.
Selling Tiago or Zanetti won't bring us more money than what we'll have to pay for D'Agostino, and wage wise we won't make a nice profit either.
Quality wise i also don't see D'Agostino bringing much more than what Tiago and especially Zanetti can offer to the team.
The only new dimension he can bring is playing as a deep lying playmaker, something we don't have in the team.
That's the only pro argument for buying D'Agostino to replace Tiago, because with D'Agostino instead of Tiago we will have everything covered in CM. We will have good ball winners, great tacklers, good passer, creative CM, pacey players, players with good positioning etc.
Personally i'm undecided on this one. If we're planning to invest good money for CM then i don't want D'Agostino. I'd prefer a box-to-box midfielder or a midfielder with similar characteristics as D'Agostino but of higher quality.
But if we don't plan to invest much and we're only looking for someone to replace Tiago, then D'Agostino is ok, i guess.