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What are the differences between 12.d3 and 12.d4 in the Ruy Lopez, Marshall counter-attack? What does white hope to achieve with each? - Quora

I Want marshall old line ie Nf6 not c6 variation - Chess Forums

What are the differences between 12.d3 and 12.d4 in the Ruy Lopez, Marshall counter-attack? What does white hope to achieve with each? - Quora

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