London & Bf4 Against the Pirc

London & Bf4 Against the Pirc

Feb 13, 2018, 8:33 AM |

When you put together a London system repertoire you have to choose what to do against the KID/Grünfeld, g6-setups.

One way is to play it in typical London fashion with Bf4, Nf3, e3/c3, h3, and focus on the queenside. This is recommended in most London books that I've seen. Yet, I've never tried doing this myself since there is a completely different, much more cunning option: the Jobava Attack with Bf4 and Nc3, threatening e4. The idea is to force Black to choose between a Grünfeld setup which occurs when he stops e4 with 3...d5 and a transposition to the Pirc which occurs when he plays the natural 3...Bg7 and we play 4. e4!. Either way, Black is deprived of his KID.

I've discussed extensively what to do when Black chooses the Grünfeld setup before (Part 1, Part 2, Part 3). Now, it's time to study how to play when Black allows the transposition to the Pirc.

The first thing to realize is that we could get our starting position from the normal Pirc move order: 1. e4, d6. 2. d4, Nf6 3. Nc3, g6. 4. Bf4. Yet, in this move order, the main dark-squared bishop move is 4. Be3 and the second main option is 4. Bg5. Let's compare all three:

To summarize what we've learned, there are four main factors to consider in the positions with Be3, Bg5, and Bf4:
  1. The d4 point. Be3 defends the central d4 point, whereas Bg5 and Bf4 don't.
  2. The e5 point. Bg5 and Bf4 both put pressure on the e5 point, the Bf4 especially allows for e4-e5 in some lines.
  3. Bishop safety (it should be obvious that White doesn't want to lose the bishop to a knight). Be3 is relatively safe, but somewhat susceptible to Ng4 (you can't really play f4). Bg5 is susceptible to h6, g5 & Nh5. Bf4 is somewhat susceptible to Nh5 (but then you can just draw it back to e3) and could get hit with e7-e5 with tempo.
  4. Kingside expansion. Be3 doesn't get in the way of anything, but doesn't really allow f4 for tactical reasons. Bg5 encourages f4, but blocks a potential g4-g5. Bf4 blocks f4, but nothing else. 
It's interesting to note that many other theoreticians besides Marin recommend Black to postpone fianchettoing with Bg7 and therefore also 0-0 in these lines, and play 4...c6 instead. However, in our move order Black frequently lacks that option since he already went 3...Bg7. This means that frequently he will not only be deprived of his KID, but he will be tricked into an objectively inferior line of the Pirc (I guess he could try 3...d6).
Let's now look at Black's main responses in this position.
1. Black is somewhat oblivious and castles immediately: 5...0-0?!
2. Black plays the familiar Pirc-move and postpones castling: 5...c6
3. Black plays the best move and puts pressure on the centre: 5...Nc6!
To sum up, if Black castles, you go 0-0-0 and play the thematic kingside attack with Bh6 & h4-h5. If Black postpones castling then you prevent them from castling altogether with an immediate Bh6. Finally, if Black plays Nc6, then you go 0-0-0 and can choose between Nf3 or building up the thematic attack slowly with f3 etc.
UPDATE: I'm adding a recently finished daily game in the 5...Nc6! line, where I played 7. f3 and Black responded with the best move 7...e5!
An interesting early d5 break has been brought to my attention. Here's MVL beating Bacrot:
Given that Black weakens the h7-b2 diagonal where the London bishop resides, and given that Black's king is still in the center, the critical and logical move is 5. Nb5!:
Black could postpone the d5 break after he has castled. Here's a game by Grischuk, again, not featuring the best move: