Italy could mutate their 3-5-2 system into 3-4-3 with Emanuele Giaccherini moving up against Spain.
The Round of 16 kicks off in Paris tomorrow at 17.00 UK time (16.00 GMT).
Antonio Candreva is out of action for this match and according to recent reports could fail to recover even if Italy go all the way at Euro 2016.
Alessandro Florenzi is stepping in to his role on the right, but there could be more surprises in store.
There are rumours that Antonio Conte could field a mobile and mutating side with Giaccherini either in midfield or pushing up to the wide right of a trident attack.
Eder can go wide left, leaving Graziano Pellè as a traditional centre-forward.
This would be why Matteo Darmian and Mattia De Sciglio are the favourites to take the left wing-back role in a 3-5-2, as they can help out more in midfield than Stephan El Shaarawy if it moved to 3-4-3.
It'd also pave the way for El Shaarawy or Lorenzo Insigne to come off the bench and harass a tiring Spain in the second half.
Italy (probable): Buffon; Barzagli, Bonucci, Chiellini; Florenzi, Parolo, De Rossi, Darmian; Eder, Pellè, Giaccherini
Spain (probable): De Gea; Juanfran, Pique, Ramos, Alba; Fabregas, Busquets, Iniesta; David Silva, Morata, Nolito
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