Qc2 Nc6 in the Nimzo Indian: key themes

 

 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2 Nc6

5Nf3 d6  (5e3 0-0 6Nge2 d6)

Keep in mind that if White tries here 6 Bg5 h6! is a very good reply as per below

White cannot play 7 Bh4 as g5-g4 wins d4. That's an important trap to be aware of.

Therefore the main line goes like this 6Bd2

6 Bd2 O-O 7. a3 Bxc3 8.Bxc3 Qe7

Here White has a few options to proceed:

9. e3 a5 (and Black will play e7-e5 next, and sometimes gets to play a5-a4 as well) 

or 9.b4 e5 10. d5 Nb8 11e4 Nh5

It is very important in this variation Nc6 when White closes d4-d5 to move the Nf6 to allow for f7-f5 counterplay: Closed center, play is on the wings !!

same idea on 9. e4 e5 10. d5 Nb8 11. Be2 Nh5 with idea f7-f5

9 g3 e5 10. d5 Nb8 11 Bg2 Ne8! with idea f7-f5

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6 a3 this is another line instead of 6 Bd2 

6.a3  6... Bxc3+ 7. Qxc3 a5 (to spot the expansion b2-b4)

8. b3 8... O-O 9. Bb2  9... Re8 

Here White has to decide how to develop Bf1.

PART I Lets see lines where bishop goes to e2 first.

10 0-0-0!? e5 11dxe5 Ne4 12 Qe3 Nc5 with Black's chances to attack the white king

10 Rd1 Qe7 11 e3 e5 12 Be2 Bg4 

Here we are following Miton,K-Perelshteyn,E 2007. 13.d5 Nb8 14Qc2 Nbd7 15 h3 Bh5 where Black played g6,Nh5-f4 and h7-h5 and h5-h4

 

 10 e3 e5 11 d5 (11de5 de5 12Rd1 Qe7 13 Be2 Bg4 14.0-0.Bh5 15 Qc2 Bg6=) Ne7 12 Nd2 c6

 (underming the center) 13 e4 b5! (striking through) 14dxc6 Nc6 15cb5 Nd4

PART II White plays g3 with idea to form a double fianchetto set-up

10.g3 e5

White has decide either to push d4-d5 or take on e5.

11d5 Nb8! 12Bg2 c6! (undermining center) 13dc6 Nc6 14 0-0 Bf5=. Black is ok here

 11de5 de5 12Bg2 

Here Black can play 12..Bg4!? with the idea take on f3 and play Nd4 next.

or Black can play 12..Qe7 and 13..Bf5 with an equal position.