The Creaking, Squeaking f2-Square.
A rook and a bishop is a powerful combination. If their joined force hits a weak point the defending side might find it hard to defend, especially if the weak point is located around the king. A very typical pawn structure arising from many openings is f2-g2-h2 or some other variation of it with the pawn on f2 (or inversely on f7). If you place a black rook on the 2nd rank and put a bishop on the g1-a7 diagonal the pawn on f2 will be a permanent weakness, unless defended by a dark- squared bishop. However, if there is no dark-squared bishop to defend the pawn, it will become a dead stop – tying the white king and rook to it. A typical endgame position is shown below.
If white gives up the pawn on f2 then his king will be permanently weak and black can organize an attack on it by moving king-side pawns forward. White’s chance is to stick to a passive defense. Black will aim to create a second weakness on the same or the other flank and use the technique of attacking two weaknesses alternately to capitalize on their advantage. In the next few games the idea of an f2- or f7-pawn pin is recurring. We will explore different defensive and attacking techniques, as well as look at historical and contemporary examples.
In the first game white managed to protect the pawn on f2 by placing the rook on a relatively active position – the f3-square. If not for the weakness on a3, it would be extremely hard for black to make progress but because such a weakness exists black went right after it. Having an extra pawn with opposite- colored bishops on the board black had to be extremely careful not to trade the rooks. It is still not an easy task to win this endgame because white can set-up the defense along light- squares. Let us see whether white succeeded in this burdensome task.
The second game is a classic played by Estonian GM Keres. He tied the black forces to the f7-pawn's defense but then unlike the previous game there were no black weaknesses on the queen-side. The pawns on b6 and a5 were protected by the dark- squared bishop. Instead, white had to create an attack on the king-side by first advancing the pawns and then moving the king forward. It was possible partially due to the passive rook position on f8.
Knowing the two previous examples it would be easy for you to come up with the solution for the next position. Black’s threat is obvious- rook entrance on d2 where it will rule the board. White can settle for the passive defense with Rf1-a4-Bd1 or play actively. Knowing the Keres game we would not want to settle for the passive defense.
Today we looked at endgame positions with rook and bishop vs. rook and bishop of opposite color where the f2 or f7- pawn was pinned and weak. In the first game we saw how the stronger side wins by creating a weakness on the opposite side of the board. In the second game there were no weaknesses on the queen-side, so Keres had to create one on the king-side. And the third game shows that it is better to be a pawn down in an opposite-color bishop endgame with tremendous drawing chances than to be tied down with an equal amount of pawns. Next week we will explore opposite colored bishop endgames in more detail.
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