The pin chess tactic freezes an enemy piece in place. Learn absolute and relative pins, deadly skewers, and how to exploit or break them over the board.
The pin chess tactic is one of the most valuable weapons a developing player can learn, because it freezes an enemy piece in place and lets you attack it at your leisure. A pin uses a long-range piece, a bishop, rook, or queen, to hit an enemy piece that shields a more valuable one behind it. Move the front piece and the valuable piece behind is exposed, so the front piece is either legally forbidden to move or practically forced to stay put.
Pins and their mirror image, skewers, turn a straight line of enemy pieces into a liability you can exploit. This guide explains the two kinds of pin, absolute and relative, then covers the skewer, shows how to pile pressure on a pinned piece to win it, and finishes with the techniques for breaking a pin when you are on the receiving end. Learn these ideas and you will control the game along ranks, files, and diagonals.
Absolute and Relative Pins
A pin needs three pieces in a line: your attacking piece, the enemy piece being pinned, and an enemy piece behind it. When the piece behind is the king, you have an absolute pin, and the pinned piece is legally unable to move, because exposing your own king to check is illegal. A knight pinned to its king by a bishop or rook is completely paralyzed until the pin is broken, which makes it a sitting target.
When the piece behind the pinned piece is valuable but not the king, you have a relative pin. Here the pinned piece can legally move, but doing so would lose the greater piece behind it, so in practice it stays. A bishop on g5 pinning a knight on f6 to the queen on d8 is a relative pin: the knight can move, but only at the cost of the queen, so it is effectively stuck. Recognizing which kind of pin you have tells you how much you can lean on it.
Pins are strongest when the pinned piece cannot easily be defended or freed, and when you have ways to attack it again. A knight pinned against the king on the edge of the board, with nowhere to run and few defenders, is often as good as won. The pin does not capture anything by itself; it sets the stage for the follow-up blow.
Skewers: The Pin Reversed
A skewer is a pin flipped around. Instead of the valuable piece hiding behind, it stands in front and is attacked first; when it moves out of the line, you capture the lesser piece behind it. Skewers are especially deadly against the king, which must always move when checked. Check a king along a rank, file, or diagonal with a rook, bishop, or queen, and whatever valuable piece sits behind it, a rook or the queen, is yours once the king steps aside.
The difference between a pin and a skewer comes down to which piece is worth more and where it stands. In a pin, the greater value is behind and the front piece is held; in a skewer, the greater value is in front and is forced to flee, abandoning the piece behind. Both exploit the same fact of chess geometry: pieces on the same straight line can be attacked through one another. Endgames with exposed kings and heavy pieces are full of skewer opportunities, so keep an eye out whenever a king wanders into the open.
Exploiting a Pin to Win Material
A pinned piece is a target that cannot run, so the winning method is to attack it more times than it can be defended. The classic technique is piling up: after pinning a knight with a bishop, bring a pawn to hit it, and if the knight is defended only once, the extra attacker wins it. A pawn thrust like h3 and g4 against a pinned knight on f6, or bringing another piece to bear, often collects the frozen piece outright.
Because a pinned piece cannot fulfill its usual defensive duties, pins also enable other tactics. A knight pinned to the king no longer guards the squares it normally covers, so you may be able to land another piece on a square it would otherwise defend, or push a pawn through a hole it can no longer cover. Great attackers use a pin as a lever: they exploit not just the pinned piece itself but everything that piece can no longer protect.
Pins are also a superb way to slow an opponent down. Pinning a defender in front of a castled king can freeze the defense long enough for your attack to arrive. The pin need not win material immediately to be worth playing; sometimes its value is the tempo and the paralysis it buys you while you bring more force to the target.
Breaking and Defending Against Pins
If your piece is pinned, you have several ways out. You can challenge or capture the pinning piece, trading it off and dissolving the pin. You can block the line between the pinning piece and your valuable piece by interposing a defender, converting an absolute pin into something manageable. Or you can simply move the shielded piece behind, so that the front piece is no longer pinned to anything and regains its freedom.
A useful defensive idea is to add a defender to the pinned piece, so that even if the opponent piles on attackers, the exchanges come out even. Another is to unpin with a counterattack, making a threat elsewhere that is more urgent than the pin, forcing the opponent to deal with your threat before they can exploit theirs. Kicking the pinning bishop with a pawn, when it does not fatally weaken your king, is often the simplest cure.
The best defense of all is awareness. Before you place a piece in front of your king or queen, check whether an enemy bishop, rook, or queen can pin it there. A little foresight keeps your pieces mobile and denies your opponent the straight-line targets that pins and skewers depend on.
Put It Into Practice
Pins and skewers become instinctive once you have set them up and suffered from them across many games. Solve puzzles that feature pinned pieces and back-rank skewers, then play games where you deliberately create lines of enemy pieces to attack. The idea travels well to Xiangqi, where the chariot rules open files and ranks exactly as a rook does, and the general's exposure along an open file can be exploited in strikingly similar ways.
On XiangqiPlay you can play, challenge opponents, and replay each game to see where a pin froze the action or a skewer won material. Start a game today, watch every open line, and make the pin one of your most dependable tools.