Nimzo-Indian Defense, St. Petersburg Variation

The St. Petersburg Variation appears when Black answers White's e3 advance by moving the b-pawn to b6. This prepares a queenside fianchetto: the bishop on c8 will develop to b7 and look along a long diagonal toward the center and White's kingside.

b6 creates a flexible plan but does not challenge the center by itself. White can develop the king's bishop to d3, the knight to f3, and secure the king. Black must connect the future bishop on b7 with a c- or d-pawn advance to exert real pressure on White's central pawns.

Nimzo-Indian Defense, St. Petersburg Variation: canonical line

1

2

3

4

5

6

7

h8

g

f

e

d

c

b

a

Start

d4

Nf6

c4

e6

Nc3

Bb4

e3

b6

The line begins from the starting position

The board replays every move in the notation maintained by the article, without adding continuations.

This variation belongs to the e3 framework of the Rubinstein System, but it is defined by a specific Black choice. It should not be confused with the Romanishin: there White plays g3 to develop the king's bishop; here Black plays b6 to develop the queen's bishop.