Master the Grunfeld Structures - Part 2
GM Mihail Marin
White plays d4-d5
Optically and not only, playing d4-d5 implies a completely different approach with respect to e4-e5 examined in the previous article. Instead of restricting the g7-bishop, White actually opens the whole long diagonal for it. This is especially effective if he had managed clearing in advance the diagonal. In our featured structure this means removing the queen's rook from the bishop's range and inducing a previous exchange on d4 so that the c3-pawn is not hanging. This can lead to a paradoxical situation when the bishop is actually useless, since attacking empty squares does not contribute to the fight. Things are different, of course, if the bishop sustains other pieces' activity, for instance of a knight could jump to b2 or c3, paralyzing White's army.
Due to the dynamic character of the opening, there is not always time for clearing the diagonal before playing d4-d5 and in many theoretical lines White sacrifices an exchange or a pawn. In order to understand whether the price is worth paying, we should mention the main virtues of advancing the queen's pawn so far.
If Black had previously played ...e7-e6 in the hope of restricting White's centre's mobility, d4-d5 implies creating a passed pawn. Whether it is strong or weak largely depends on each side's piece placement and activity. With the pawn on e7 still, the central advance could cause some discomfort to Black's knight (usually developed on c6) and allow the occupation of the c6-square (if Black had advanced his b-pawn).
On the negative side of this typical operation we have three main elements.
1) In the systems with Ng1-e2, handing in the control over e5 could lead to strong black initiative after ...Nc6-e5. True, if White manages to extinguish it, Black would soon be crushed by White's space advantage.
2) The second aspect refers to the relative weakness of the daring pawn. After losing the support of his colleague from the c-file, the intruder could easily be lost if his advance is not properly sustained by pieces.
3) Finally, even if after ...exd5, exd5 White manages defending his passer with c3-c4, a blockading knight on d6 could well yield Black a favourable ending.