Chess Opening Theory/1. d4/1...Nf6/2. c4/2...e6/3. Nc3/3...Bb4/4. a3
|Moves: 1.d4 Nf6 2. c4 e6 3. Nc3 Bb4 4.a3|
|ECO code: E24-E29|
|Parent: Nimzo-Indian Defence|
Nimzo-Indian Defence, Sämisch Variation 
Sämisch Variation 
With 4.a3, the Sämisch named after the German Grandmaster Friedrich Sämisch, White immediately questions the placement of the bishop. This has the benefit of seizing the bishop pair early (if Black takes the knight), and resolving central tension. White will play for an eventual e4 push after f3.
Taking the Knight is pretty much an automatic response at master level as the alternative lose a tempo or lose a piece.
- 4...Bxc3+ inflict the doubled pawns on White.
- 4...Ba5?? Maintaining the pin is an error as it just loses the bishop after 5.b4 Bb6 6.c5.
- Playing 4...Be7?! is better, but it defeats the point of the Nimzo-Indian since White gets to play 5.e4 for free. (The point of the 3...Bb4 pin was to prevent White from doing this easily.)
Theory table 
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4.a3
When contributing to this Wikibook, please follow the Conventions for organization.
- Nunn's Chess Openings. 1999. John Nunn (Editor), Graham Burgess, John Emms, Joe Gallagher. ISBN 1-8574-4221-0.
- Batsford Chess Openings 2 (1989, 1994). Garry Kasparov, Raymond Keene. ISBN 0-8050-3409-9.