The Queen's Gambit, 1.d4 d5 2.c4, has at its heart a simple strategic idea, that of exchanging the white c-pawn for the black d-pawn and then establishing a centre with a later e2-e4. There are a number of ways black can meet this idea, but they tend to fall into a small number of distinct categories:
1) Preventing white from carrying out this plan in the first place by defending the d5 pawn with a pawn: this is mostly the province of the Queen's Gambit Declined, 2...e6 3.Nc3 Nf6/Be7, although there are some lines of the Slav, 2...c6, which could also fall into this category.
2) Allowing white to carry out his plan, but only at the cost of a pawn: this idea arises in lines of the Slav, 2...c6, and semi-Slav, 2...e6 3.Nc3 c6; this usually requires white to consciously play one of the gambit lines, otherwise the play will mutate into cases 1) or 3).
3) Allowing white to carry out his plan, but exploiting the weakness that arises as a consequence of it, namely the semi-backward and somewhat weak pawn on d4. This is the strategy of the Queen's Gambit Accepted, 2...dxc4, and the Chigorin, 2...Nc6 (see the diagram on the left).
So what are the ideas behind the Chigorin? Well, two stand out immediately: the idea of playing ...dxc4 followed by capturing on d4, and that of playing ...e5 thanks to the support from the knight on c6. For example, if white plays 3.Nc3, black can reply with 3...dxc4, and then 4.d5 Na5 renders it rather tricky for white to get the pawn back, whereas 4.e3 allows black to immediately break in the centre with 4...e5.
The obvious counter to both those ideas is the development of the other knight with 3.Nf3, which is what I played against Tim Seymour in our game at Coulsdon. His response was to renew the threat against the d4 pawn with 3...Bg4, after which I played 4.cxd5. Now 4...Qxd5?! would allow easy development of the white pieces with gain of tempo after 5.Nc3 (this is generally applicable to the Chigorin, incidentally: if white can play cxd5 Qxd5 Nc3 without the knight's being pinnable with ...Bb4, he's probably got a good game), so Seymour played 4...Bxf3, after which I had a choice.
I could either play 5.gxf3 Qxd5 6.e3, after which 6...e5 leads to double-edged play, or I could play 5.dxc6 Bxc6 6.Nc3 e6 7.e4. This is what happened in the game, giving me the position shown above here.
The pawns on d4 and e4 form an impressive classical centre, but they are easily attackable, and this informs black's choices over the next few moves: 7...Bb4 8.f3 (the only reasonable way to defend the e4 pawn; 8.Bd3? would drop the d-pawn) Qh4+! 9.g3 Qh5 (now the f3 pawn is another pawn I have to worry about) 10.Be3 0-0-0 (note that the rook is developed straight into an attacking position against the d4 pawn) 11.Bg2 f5, and we have the position above. Notice that my impressive centre is still there, but black has developed nearly all his pieces to squares where they attack it directly or indirectly. (The knight will be coming to f6 to attack the e-pawn.)
The position here is certainly full of tension, and it's a shame that the actual game was then a bit of a let-down; just a few moves later, black made a blunder which converted his temporary sacrifice of the e-pawn (he has no good way to defend it after I play 12.Qb3) into a permanent one, and I won in fairly short order in the endgame.
Openings and endings
2 years ago