The rock solid 9…b6 Karpov Variation is a tough nut to crack. The main position arises after

1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 0–0 5.Bd3 c5 6.Nf3 d5 7.0–0 cxd4 8.exd4 dxc4 9.Bxc4 b6 10.Bg5 Bb7 11.Re1

Sokolov,I examines this position deeply in The Stratgic Nimzo-Indian(NIC 2012). Let us examine a key recent game. to see the impact on published analysis.

Potkin,V (2684) – Harikrishna,P (2665) [E54]
74th Tata Steel GMB Wijk aan Zee NED (7), 21.01.2012
Sokolov considered 18..e5 but black played 18…Qd6 which resulted at least an equal game.

Critical Position 1 The position is tense. The long diagonal has been blocked with f3. The Nh5 looks offside and perhaps deserves a bigger role. Is the time for quiet play or concrete play? Perhaps there is a combination based on the inconvenient lineup of Re8 vs Qe2 on the e-file. What should black do?

Black to play