Relative Pin - chess tactic
Relative Pin
Definition
A relative pin is a tactical motif in which a piece is “pinned” to a more valuable friendly piece (usually the queen or a rook) but not to the king. Because moving the pinned unit would expose the higher–value piece behind it, such a move is legal yet normally undesirable. This contrasts with an absolute pin, where the king is the piece behind the line, making it illegal for the pinned piece to move under the laws of chess.
Basic Mechanics
- Three pieces are aligned on a rank, file, or diagonal: the attacker, the pinned piece, and the more valuable piece.
- The attacking piece must be a bishop, rook, or queen (the only long-range pieces capable of pinning).
- The pinned piece can legally move, but doing so will typically cost material or allow a decisive attack.
- The pin is broken by
- moving the more valuable piece away,
- interposing another piece between the attacker and defender, or
- capturing or deflecting the pinning piece.
Strategic Significance
Relative pins are among the most common tactical devices in practical play. They are used to:
- Restrict mobility – the pinned piece often loses its defending power.
- Accumulate pressure – attackers can pile up forces on the pinned piece, forcing concessions.
- Create combinations – motifs such as overload, deflection, and double attack frequently hinge on an existing relative pin.
- Induce weaknesses – defenders may contort their structure (e.g., moving pawns or pieces awkwardly) to escape the pin.
Historical & Theoretical Notes
The concept was already cataloged in the 17th-century manuscripts of Gioachino Greco, but it was Aron Nimzowitsch who formalized its strategic importance in his 1925 classic My System. He coined the aphorism “The pin is stronger than the bayonet,” stressing that a pinned piece can be rendered harmless for many moves—sometimes an entire game.
Illustrative Mini-Position
Set the pieces on an empty board:
- White: Kg1, Qd1, Rf1, Bc4, Nf3, pawns on g2, h2.
- Black: Kg8, Qd8, Be6, Rc8, Ng8, pawns on g7, h7.
Black plays 1…Bxc4 2. Qxd8+ Rxd8.
Now Black’s bishop on e6 pins White’s knight on f3 to the queen on d1—a
relative pin. If 3. Nxe5? (ignoring the pin) Black replies 3…Rxd1
winning the queen and the game. White must first remove the queen or
challenge the bishop.
Famous Game Spotlight
Tarrasch – Nimzowitsch, St. Petersburg 1914 featured a textbook relative pin. In the middlegame Nimzowitsch played …Bg4, pinning a white knight to the queen. Tarrasch eventually moved the knight, sacrificing his queen for dynamic compensation—proof that even in a relative pin the defender can sometimes break free if the resulting imbalance is worth it.
Common Tactical Themes Emerging from a Relative Pin
- Pin and Win: Attack the pinned unit repeatedly until it collapses.
- Overload: The pinned piece is also a key defender of another target.
- Deflection/Sacrifice: Luring the more valuable back-piece onto a square where it can be captured or forked.
- Breaking the Pin: Temporarily giving material to eliminate the pinning piece, then regaining it later.
Example in PGN Format
The next eight moves create a relative pin against the white knight on f3.
Interesting Facts & Anecdotes
- The German term relative Fesselung (relative shackle) became popular among early 20th-century problem composers.
- Some top players, including Mikhail Tal, were famous for deliberately moving a relatively pinned piece if it unleashed a bigger attack—showing that all chess rules have exceptions in practice.
- Engines evaluate most relative pins as an immediate plus only if the attacker can increase pressure; otherwise, today’s defensive resources (like precise counter-attacks) often nullify the tactic.
Key Takeaways
- A relative pin restricts but does not forbid movement.
- Exploiting it typically demands building additional threats; the pin alone rarely wins.
- Never accept a relative pin passively—seek to unpin, counter-attack, or transform the position.