4.Qc2 O-O 5.a3: the main line with 6...b6 is variation 1 of 6 in the Against the Nimzo-Indian and Queen's Indian course, a advanced opening course for White (ECO E32). It runs 21 moves and begins 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2 O-O …. Black castles and gives the bishop for the knight. White takes back with the queen and keeps the bishop pair. Then White pins with the bishop on g5 and fights for e4 with the f-pawn. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. d4 – White takes space in the centre.
1... Nf6 – Black develops and keeps an eye on e4.
2. c4 – White grabs more space and attacks d5 from the side.
2... e6 – Black opens the f8 bishop and keeps both Indian defences in reserve.
3. Nc3 – White prepares to push the e-pawn to e4.
3... Bb4 – The Nimzo-Indian. Black pins the c3 knight and fights for e4.
4. Qc2 – The Classical Variation. The queen guards c3, so White can take back with the queen and keep a good pawn structure.
4... O-O – The most common reply. Black castles first and waits to see White's plan.
5. a3 – White asks the bishop at once. Black must take or retreat.
5... Bxc3+ – Black gives the bishop for the knight.
6. Qxc3 – White takes back with the queen. White has the bishop pair and no weak pawns.
6... b6 – Black puts the bishop on b7 to fight for e4 and the light squares.
7. Bg5 – White pins the f6 knight. It is now harder for Black to control e4.
7... Bb7 – Black develops the bishop to the long diagonal.
8. e3 – White opens the f1 bishop and gets ready to develop the kingside.
8... d6 – Black keeps the centre closed and prepares the queen's knight on d7.
The lesson goes on for 5 more moves, each with its explanation.
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