Critical Point

During my last game at the Rapid competition at the chess club at Ryde-Eastwood RSL, my opponent and I arrived at the position shown (see 1st picture on right). White to play.

In this post, I am going to highlight my thought process.

Now there are no immediate tactics to be played here. Both of us have about 15 minutes of time left so there was no need to rush.

Strangely, I had the feeling that I am either at a critical juncture in this position or very close to it so I sank into a deep thought here for about 5 minutes.

(Fritz evaluates this position as even)

While looking at the position, what are the things to note?

1. My attack has stalled. Currently there's no way to continue any further development down the kingside. In fact, my Knight is doing a fine job stopping the Black rooks from infiltrating the position. So there's no way I am going to move my nice Knight on g5.

2. I have an advantage of space. How do I convert that advantage? For now, I cannot see any.

3. What are Black's threats?

Black has 3 main threats (see 2nd picture on right).

a. He threatens 1... Ba6 (red arrows) after attacking my Knight on d3 and if I play Bf1, my position easily falls to pieces if I allow him to put his bishop on c4 and my King would be in a direct line of fire from his Rook on g7.
b. He threatens 1... Nb5 (green arrows) attacking d4 pawn which is weak.
c. He threatens 1.... Nh6 (green arrows) with follow up of Nf7 and taking my Knight on g5 to open the g-file for his Rooks.

My weak squares are highlighted in yellow.

b5 and d4 as mentioned above. But in addition, the square on e4 is weak. If there was a minor piece there, I would have to attack it with one of my pieces either with my Knight on g5 or my Bishop on g2, running a potential risk of exposing my King down the g-file. h4 is also weak. If the black pawn on h5 pushes to h4, my square g3 becomes weak. For now, these 2 squares are hard to access so they don't pose a problem at the moment.

4. Is it possible to counteract them? Yes. Pushing the a pawn to a4 stops both of Black's plans (a) and (b).

What are the advantages of pushing the a-pawn?

If Black plays 1...b4 2. Nc5+ is winning with either a potential forking of the 2 Rooks after 3. Ngxe7 Nxe7 4. Nxe7 or taking the Bishop with 3. Nxb7.

If Black plays 1...Ba6, 2. b5 is crushing.
If 2.... cxb5 3. Rxc7+ Kxc7 4. Nb4! (hitting the Bishop on a6 - there's no rush to forking the Rooks) and once the Bishop moves, 5. Nxe7 winning the Rook and threatening 6. Bxd5
If 2.... Ba6 3. bxc6+ Bxc6 4. Nb4 Bb7 and the Rxc7+ tactic occurs again.

At that point, I played 1. a4, my opponent got pressured under time control a few moves later and made an unfortunate critical mistake and it was enough for me to convert my advantage.

Incidentally, if Black had responded to 1.a4 with 1... Rc8 (see 3rd picture on right). It would have been hard for me to break through and a draw might have been the result.