How to play vs. 1.e4 e5 2.Nf3 Nc6 3.Bc4 d6? As title above, how to play vs. 

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1.e4 e5 2.Nf3 Nc6 3.Bc4 d6 


I see that this move (3...d6) is generally considered inferior in books, or not even mentioned in books about 3.Bc4, but I cannot see a clear way to obtain advantage.
The game will get the characteristics of the Philidor Defense rather than the Italian Game. Wikipedia calls it the Semi-Italian Opening.


  I. A. Horowitz called the defence "solid", also writing: "It does not seem quite sufficient for equality."


The Wikipedia article notes several possible continuations for White, with 4. d4 probably the best bet for advantage.