Russian Opening (aka Petrov Defense)

The Petrov Defence may look like a counter-attack, and very early on this was supposed to be the idea. However, it soon became apparent that the symmetrical nature of the opening produced defensive positions. If White takes the pawn, Black should avoid taking it back because of 4. Qe2 Nd6?? 5.Nc6+ which wins the black queen. The main line goes 3. Nxe5 d6 4. Nf3 Nxe4. It is considered quite solid, and is a key defensive opening against the dangerous first move 1. e4. There are a few gambits which White can try to shift the style of the opening. The Cochrane gambit is perhaps the most dangerous. It involves a Knight sacrifice on f7. Currently not considered objectively sound, its use is psychological: White dares the opponent to spend twenty moves defending against an attack, and this pressure may cause the Black player to finally fall victim to a tactical shot.

Sources:<http://en.wikibooks.org/wiki/Chess/Basic_Openings#Russian_Game_.28aka_Petrov_Defence.29>

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