Lesson 12: Pin and Defender Removal
A pin is a situation that is similar to a skewer. One of your ranging pieces has two of your opponent’s pieces in its path (usually a less valuable piece in front and a stronger piece behind it). There are two main kinds of pins: (1) Where the first piece is being defended by another piece, making it impossible to capture immediately, and (2) Where the first piece is in front of the king.
Diagram A shows the first type of pin. Sente’s bishop is attacking the lance on 44 and is also aiming at the bishop on 22. However, because the bishop is supporting the lance, sente cannot immediately take the lance. The lance is said to be “pinned” to the bishop. You can take advantage of this type of situation.
If you have a pawn in hand, you can take advantage of the pin by playing ?P*45. If gote takes the pawn with ?Lx, then ?Bx22+ wins the bishop for free. If he ignores it, ?Px54 wins the lance.
So what if you want to take the pinned piece rather than the piece it’s pinned to? In this situation, you can use a technique called “defender removal.” Let’s say you want to take gote’s silver, and you have 3 pawns in hand. ?P*23 ?B-11 ?P*12 ?B-33 ?P*34 and the bishop is now forced to run, otherwise it will be captured. After the bishop retreats from its diagonal, ?Bx44 wins the silver.
The second kind of pin will force a piece to stay attached to the king.
Let’s say gote is attacking hard on the third file, and using his tokin, he will be able to promote his rook in the next few turns, such as in Diagram D. You can stop this in Diagram D with ?B*24! His attack is put to an end because the rook cannot legally move away from the king.