Chess Opening Theory/1. d4/1...d5/2. c4/2...c6/3. Nc3/3...dxc4/4. e3/4...b5

< Chess Opening Theory‎ | 1. d4‎ | 1...d5‎ | 2. c4‎ | 2...c6‎ | 3. Nc3‎ | 3...dxc4‎ | 4. e3
Slav Defence
a b c d e f g h
8a8 black rookb8 black knightc8 black bishopd8 black queene8 black kingf8 black bishopg8 black knighth8 black rook8
7a7 black pawnb7 black kingc7 black kingd7 black kinge7 black pawnf7 black pawng7 black pawnh7 black pawn7
6a6 black kingb6 black kingc6 black pawnd6 black kinge6 black kingf6 black kingg6 black kingh6 black king6
5a5 black kingb5 black pawnc5 black kingd5 black kinge5 black kingf5 black kingg5 black kingh5 black king5
4a4 black kingb4 black kingc4 black pawnd4 white pawne4 black kingf4 black kingg4 black kingh4 black king4
3a3 black kingb3 black kingc3 white knightd3 black kinge3 white pawnf3 black kingg3 black kingh3 black king3
2a2 white pawnb2 white pawnc2 black kingd2 black kinge2 black kingf2 white pawng2 white pawnh2 white pawn2
1a1 white rookb1 black kingc1 white bishopd1 white queene1 white kingf1 white bishopg1 white knighth1 white rook1
a b c d e f g h
Position in Forsyth-Edwards Notation (FEN)
Moves: 1. d4 d5 2. c4 c6 3. Nc3 dxc4 4. e3 b5

4...b5

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This guards c4 and is the best move. The queenside weaknesses are not a problem, as the knight on c3 is vulnerable to b-pawn attacks with ...b4. Note that Nxb5?, trying to exploit the long diagonal to destroy Black's queenside, is a mistake, and gives black two roads to an advantage. Often, Black will play b4, to boot white's knight away, and not try to hold c4.

When your opponent has a spatial plus, you want to use pawn breaks. Since b3 Qa5 (b4 Na4 c3 is also good) is annoying, the only other break is 5.a4. Therefore, the best move is 5.a4.

Theory table

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5 6 7 8
Nxb5?

cxb5

Qf3

Qc7!

Qxa8

Bb7

Qxa7

e5

-/+
...

Nc6

Qxc6+

Bd7

Qf3

e5!

-/=
a4

b4

Ne4

Qd5

=