3...a6 (C77: Morphy Defence)
- Black want to know immediately about White intention in attacking Black Knight on c6.
- So, Black force White to reveal his/her intention by attacking Bishop and give option between exchanging Bishop for Knight or retreat from Black Pawn attack.
- Note, retreating Bishop to Bc4 is inferior move, because that position can be reached earlier with 3. Bc4 not with 4. Bc4.
- Retreating with 4. Bc4, give Black free a6 move.
- White usually retreat to a4 to continue attacking Black Knight or capture Black Knight on c6.
White Responses
- White maintain attack and possibility pinning Black Knight against Black King, if Black move d pawn.
- Retreating White Bishop into Bc4, Bd3 and Be2 is inferior moves, because White Bishop can go into that squares earlier without going into Ruy Lopez.
- Retreating White Bishop into Bc4, Bd3 and Be1 give Black free a6 move.
- White capture Black Knight on c6, therefore removing protector of Black e pawn.
- By Playing Exchange Variation, White trying to damage Black Pawn Structure (inflicting double pawn on c file), because in the next move Black should capture White Bishop with either b pawn or d pawn.
- If Black didn't capture White Bishop, then Black will lost material without proper compensation.
- Capturing With Bishop with either b pawn or d pawn, make double pawn in c file.
Black responses to 4.Bxc6
4...dxc6
- Capturing White Bishop using d pawn is better than capturing using b pawn.
- Capturing White Bishop using d pawn counter White threat of capturing Black Pawn on e5.
- If White dare to capture Black Pawn on e5, then Black Queen fork White Knight and Pawn by playing 5...Qd4.
- The result of Black Queen fork is restoring material balance and put Black in good position.
4...bxc6
- Capturing White Bishop using b pawn considered inferior than capturing using d pawn.
- Capturing White Bishop using b pawn, did not open way for Black Queen to counter White threat of capturing Black Pawn on e5.
- Therefore, Black should find another way to restore material balance if White captured Black Pawn on e5.
