A Good Defense Against the London System: A Case Study

The London System or Mason Variation is one of the strongest openings for White that I have encountered that gives White many winning chances. It's characterized by 1. d4 and by an early development of the dark squared bishop to f4 as well as a strong pawn pyramid (c3, d4, and e3) that takes control of the center and makes it very difficult for Black to play against it. This opening was made popular by Magnus Carlsen, who has had great success playing it. It's the ire of many Black players and has been criticized for not allowing dynamic play. So how can Black play successfully against it? 

The strengths of the London System is the pawn pyramid and the dark squared bishop that protects those pawns on the dark squares. If Black can undermine both of these things, they can have a game with good winning chances. A game I recently played is a good example of an opening setup in which Black can ruin the pawn pyramid structure and take out the dark squared bishop.  Here is the game: 

1. d4 Nf6: When Black plays Knight to f6 it allows them to keep their options open and I wanted to have the flexibility just in case 2. Bf4 was played. 

2. Bf4 c6: White develops their dark squared bishop to f4, while I play c6 to prepare to develop my Queen to b6.

3. e3 Qb6: White continues to assemble the pawn pyramid, but I have developed my Queen to b6 and attacking the vulnerable b2 pawn. This pawn is the key because it protects c3 in the pawn chain. White is forced to protect this pawn, either by using the Queen to defend it on c1, which is not a good use of that piece. The other option is to play b3, which protects the pawn but weakens the pawn chain and opens up the a1-h8 diagonal. As you will see, that is something I took advantage of. 

4. b3 d6: White decided to defend the b2 pawn by playing b2-b3. I play d6 in preparation of trapping the dark square bishop on f4, when White plays Nf3 and the White Queen's line of attack is blocked.

5. Nf3 Nh5: White played Nf3 which makes it now possible for me to play Nh5 and trapping the dark squared bishop. 

6. Bg3 Nxg3: White played Bishop to g3 and it was captured by my Knight. Now if White had played Bishop to g5, I could have played h6. The bishop would inevitably be captured but by just playing Bg3, they can have an exchange of pieces. 

7. hxg3 g6: White now has doubled pawns and the h file is open. I played g6, preparing to fianchetto my dark squared bishop to g7 and control the a1-h8 diagonal.

8. c3 Bg7

9. b4 O-O: Knowing that a solid pawn pyramid is not possible and there is no dark squared bishop to protect it, White decides to create a stonewall pawn structure of e3, d4, c3, and b4.

10. a4 e5

11. Ng5 exd4: I begin to break down the stonewall pawn structure with exd4.

12. exd4 Re8+ 

13. Be2 c5

14. a5 Qb5: Qb5 was a mistake on my part and I lost a tempo after Na3

15. Na3 Qd7

16. bxc5 dxc5

17. dxc5 Bxc3+: By taking my pawn on c5, White reveals an attack on my Queen and opens up the a1-h8 diagonal. Since I am down a pawn, I do not want an exchange of Queens so I captured the pawn on c3, forking both the King and the Rook for a material gain. If White so chose to exchange Queens after I capture the Rook, I would be up material. 

18. Kf1 Bxa1 

19. Qxa1 Qe7: I played Qe7, threatening Qxe2+

20. Rxh7 Qxe2+: Rook takes h7 was a mistake by White. Their idea was to create a checkmate threat with Qh8#. But the Queens will be off the board after 20...Qxe2+ 21. Kg1 Qe1+ 22. Qxe1 Rxe1+. Instead Black should have played 20. Bc4. If that variation happened, I would have played 20...Qxg5 21. Bxf7 Kxf7 22. Rxh7+ Ke6. 

21. Kg1 Qe1+ 

22. Qxe1 Rxe1+ 

23. Kh2 f6 

24. Rh6 fxg5

25. Rxg6+ Kh7 

26. Rxg5 Nc6 

27. Nc2 Re6 

28. Nd4 Nxd4: Desperate attempts by White to try to attack my pieces. 

29. Rh5+ Rh6: I block the check, but also pin White's last rook to his King. If he captures my Rook, I can recapture with my King and I have one Rook and two minor pieces and pawns, while White just has a King and pawns. 

30. Kg1 Rxh5: Kg1 was a dubious move and after my Rook takes White's last rook on h5 White had had enough and resigned. 

0-1 Black Wins

My opponent played well and this was a good game and it demonstrates that there is way to beat the London System and have good chances as Black. I hope this example helps and that you try this opening setup in your next game against the London System.