Heritage in Modern Play, Part 6

In chess, like in life, there are common beliefs that are not necessarily true or based on solid evidence but nevertheless survive the passage of time and continue to be widely accepted as true. Growing up in a "chess country" like Ukraine, I heard many chess dogmas from older chess players, and one of the rules that I could not understand well at the time was that a knight is badly placed on b3 or, for Black, b6. It makes sense why a knight is badly placed on a3 because that is the edge of the board, but on b3, and why not b4 for example?

I guess that the way openings are played, a knight almost never ends up on b4, as compared to b3. Now that I come to think of it, probably this belief has some ground to it. The knight on b3 can be easily limited by the opponent by moving his pawn to b6, when both the a5- and c5-squares are no longer available. A similar thing can happen to the knight on c3 if Black pushes a pawn to c6, however then White has the extra option Na4-c5, which he doesn't have if the knight is on b3.

Today's topic is the rook pawn push to chase away the knight from its position on b3/b6 or g3/g6. Usually the following rules apply:

1. First, the side who plays against the knight limits its maneuverability by pushing the pawn three squares away from it. For example, it would be a b6-push if the knight was on b3.
2. Chasing away the knight with a rook pawn is often a good idea when the knight is controlling important squares. For instance, a knight is on g6 might control important squares on an open file e-file.
3. Generally, g3-h4-Kg2 structures are great for endgames, hence White tries to achieve this structure and if the h5-push is advantageous then it will always be in the air.
4. If the pawn push leaves the knight on the eighth rank immobile, then White can proceed to break through on the opposite flank (see Shirov-Anand below).

As always, we will start from the classics and later see several examples from modern play. The first example is clean-cut and follows a line of strategy that is easy to follow. Botvinnik, who plays the white pieces, has a solid advantage as his pawn structure is better and he has control of the only open file. However, the two important squares that he can use to regroup his pieces or claim even more territory are under control of Ng6. Hence, to improve his position even further he chases away the knight, exchanges pieces what favors him and wins with an active rook on the seventh rank.

The following example is straightforward as well. Botvinnik's position is close to winning; besides having all the advantages as in the previous example, he is also up a pawn. There are many ways of winning this position but he chooses the method we already know from the previous game: pawn advance.

In the following example from another great classic, Smyslov uses the same pawn push but for different reasons. Besides controlling the e5-square the knight on g6 is useless. Smyslov's main advantage is control of the c-file. However, his pawn structure is inferior due to the isolated d-pawn. Because the game is heading to an endgame this can become an important consideratio

For now, Smyslov decides to improve his position and the h4-push does exactly that. Black should have exchanged a pair of rooks to weaken White's pressure on the c-file. Instead, he decided to improve his pawn structure on the kingside with h5-g6 pawn pushes that ended up weakening his king. This allowed White to create a strong attack.

In another Smyslov game, the h4-h5 push happens in the endgame, where the only purpose of the knight on g6 is the defense of the e-pawn.

Now let us look at two positions from modern practice. Anand, in the following example, restricts Nb3 with a b6-push and is preparing an invasion on the c-file. White did manage to hold on and to build a defensive set-up at the price of the knight being excluded from play on a1. Anand proceeded to break through on the kingside, where he had more pieces.

I have a memorable example from my play from the past World Open. In the position below I considered two options, Nb6 or Nc5, each one having plusses and minuses. Nc5 attacks the e4-pawn and the knight is very actively placed there. On the other hand, Nb6 encourages White to trade bishops. Which one to choose? Had I seen the b3 rebuttal from White, I would have played Nc5 without thinking much, as after the b3-move my knight was doomed to remain passive.

Next week we will continue with the series on heritage in modern play.