Chess Opening Theory/1. d4/1...Nf6/2. c4/2...e6/3. Nc3/3...Bb4/4. Qc2/4...d5

4…d5 Nimzo-Indian Defense: Classical, Noa Variation rd nd bd qd kd rd pd pd pd pd pd pd pd nd pd bd pl pl nl pl pl ql pl pl pl pl rl bl kl bl nl rlThe Noa variation is the third most played and second most combative way of playing the Classical/Capablanca variation in the Nimzo-Indian; second to 4…c5, the Berlin variation. The point of the Noa variation is that, if white captures the d pawn (the most played line at master level) 5.cxd5 5…exd5 6.Bg5 6…h6 7.Bh4 and 7…g5! comes in. After the bishop retreats with 8.Bg3, the knight leaps forward with 8…Ne4!. In this position, Black has an incredibly weak kingside, but has great compensation due to the activity of the pieces and whites position being frozen up with the knight pinned to the king, and the bishop on a passive square. Going back to the start of the variation with 4…d5, a much more solid approach for white seems to be 5.a3, essentially forcing an exchange of a bishop for a knight, however, in the ensuing lines (e.g. 5.a3 5…Bxc3 6.Qxc3 6…O-O 7.Bg5) black eventually takes the pawn with 7…dxc4 and after the queen takes, it is exposed to an incoming attack from the white bishop after black plays b6 and Ba6. Theory table 5. cxd5 5. exd5 6. Bg5 6. h6 7. Bh4 7. g5 8. Bg3 8. Ne4 5. a3 5. Bxc3+ 6. Qxc3 6. Noa variation, Pretzel Gambit 5. ... 5. ... 6. bxc3