Pin

A pin occurs when a piece of lesser value cannot move because its movement would expose a piece of stronger value behind it. The piece is then said to be “pinned”. Let’s take a look at a couple of examples…

Stupak(2458) – Tihonov(2460)

Ch-BLR, 2009 

In this position White played 30.Bxc5! and now if 30…dxc5 31.f4! would lead to White recovering the minor piece and holding onto his extra pawn with a crushing position. In the position after 30.Bxc5 the knight is pinned to the rook since its movement would mean the rook is exposed to Rxe8. Here is a somewhat trickier example:

Zhao Xue(2517) – Beliavsky(2638)

6^th Gibltecom Masters, 2008 

Black to move, Beginner puzzle from KEBU Chess Tactics Software 2009

In this position the grandmaster made use of the pin two times. After 32…Bxg4! The bishop cannot be captured by the knight because Black could then capture the queen. (A queen and pawn is usually stronger than a rook and bishop) Thus, the knight is “pinned” to the queen. But what if 33.Qxg4 is played? That is what was played in the game but then Black played 33…Rg8! Another pin. The queen is lost because moving her would expose the king (and this is illegal).

These examples were taken from games played very recently (last year) directly from KEBU Chess Tactics Software. You can download a free version here for more puzzles like these.