Chess Opening Theory/1. e4/1...c6/2. d4/2...d5/3. Nc3/3...dxe4/4. Nxe4/4...Bf5/5. Ng3

= Caro-Kann Defence:Classical Variation =

Bg6 is almost always played as the only sensible place for the bishop to retreat to, although defending the bishop with g6 is a very rare alternative, leaving black with an inferior pawn structure.

Theory table
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1.e4 c6 2.d4 d5 3.Nc3 dxe4 4. Nxe4 Bf5 5. Ng3