Currently we have 5 midfielders for 2 spots - Locatelli, Thuram, Koopmeiners, McKennie, and Miretti.
We have 3 wingbacks for 3 spots - Joao Mario, Cambiaso, and Kostic (4 if you count Rouhi). 5 if you include Nico who looks to on the way out.
We have 7 defenders for 3 spots: Savona, Kalulu, Gatti, Bremer, Rugani, Kelly & Cabal. (only Kelly & Cabal are lefties).
We have 3 attacking forwards/wingers for 2 spots. Conceicao, Yildiz, and Adzic - 4 if you include Nico who is on his way out.
We have 2 center forwards for 1 spot. David & Vlahovic. I don't count Milik for obvious reasons.
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So if you believe Nico goes (who can cover 2 spots - wingback and attacking winger on either side), I would argue we need 2 players. A wing back and an attacking forward. Nico is a jack of all trades and master of none. His 3 main strengths are his versatility, work rate, and arial ability. His weaknesses are pretty much everything else.
The 2 big crucial events are Nico and Dusan and our incoming would change dramatically if they stay or go. If they both go, I would expect us to get Muani, Zhegrova and wingback and possibly even a left footed defender given how much we save from having Dusan off the books. If Dusan stays, forget about Muani.
If both stay, I think we may just end up with 1 more signing and that would be Zhegrova and maybe a low cost wing back option. To me this is crucial because only Yildiz and Conceicao are the only players we have who can beat their man in a one on one and that is important especially in games where teams like Parma park the bus. Zhegrova has proven to be capable of doing this.
If Savona is sold, I think they would go for a left footed center back like Beraldo, Balerdi or Kiwior. I don't see us selling Kelly for 3 reasons: 1) Tudor seems to trust him; 2) He is only 1 of 2 left footed center backs where the other is unproven and coming off a big injury, 3) His wage is low and its unlikely we will make much from his sale compared to what was paid.