Zwischenzug (intermediate move) — definition
Zwischenzug
Definition
A zwischenzug (German for “intermediate move”) is a surprising move played in between an expected series of captures, checks, or threats. Instead of replying directly to the opponent’s threat, the player inserts a move of their own—often a check or a sharper counter-threat—that forces the opponent to respond, thereby improving the eventual outcome of the original sequence. In English-language literature you will also see the terms “intermezzo,” “in-between move,” or simply “zz.”
How It Is Used
- Tactics: The zwischenzug frequently appears in forcing tactical lines where a direct recapture would be inferior. By changing move order, the player may gain material, avoid a worse position, or transpose into a favorable endgame.
- Defensive Resource: When under attack, a well-timed intermediate move can interrupt the opponent’s combination, buying time to resolve threats later on more favorably.
- Psychological Weapon: Because the move order is unexpected, a zwischenzug can sow confusion and induce blunders, especially in time pressure.
Strategic Significance
While often tactical in nature, the zwischenzug embodies a deeper strategic lesson: chess is not always a linear exchange of threats. The side that controls the tempo can dictate how and when sequences unfold. Mastery of intermediate moves cultivates calculation skills, visualization, and an appreciation for forcing moves—cornerstones of strong play at every level.
Historical Notes
The concept has been recognized for centuries, but the German term gained wide currency in the early 20th century through analytical works by Siegbert Tarrasch and later writers of the Hypermodern school. Annotators such as Richard Réti and Aron Nimzowitsch popularized the phrase, finding it more precise than existing English equivalents.
Classic Examples
1. Tarrasch – Nimzowitsch, St. Petersburg 1914
After 20...Nxd4, White might automatically intend 21.cxd4, but instead played 21.Qe8+!—an intermediate check winning material. Only after Black’s forced reply 21...Rxe8 does White recapture on d4, emerging a piece ahead.
2. Karpov – Kasparov, World Championship (Moscow) 1985, Game 16
Position after 22...Rxe5: Many spectators expected 23.dxe5, but Karpov uncorked 23.Qa8+! (zwischenzug). Once Kasparov parried the check with 23...Re8, only then did Karpov capture on e5, equalizing the game.
3. A Miniature for Study
Consider the following short tactical line, suitable for club players to practice spotting zwischenzugs:
Black expects 18...Qxd8 but is instead checkmated after the zwischenzug 18.Rd8+!
Tips for Recognizing or Executing a Zwischenzug
- Look for forcing moves (checks, mates, strong threats) before making an “obvious” recapture.
- Examine every capture twice: first in the expected order, then by inserting an alternate move for you or your opponent.
- Keep track of tempo; if the zwischenzug is not forcing, the opponent may ignore it.
- During calculation drills, deliberately practice spotting candidates that change the move order.
Fun Facts & Anecdotes
- The plural in German is Zwischenzüge, but English writers rarely add the umlaut, leading to hybrids such as “zwischenzuegs.”
- In blitz commentary, grandmasters often shout “Zwischi!” as shorthand when they see an intermediate move on the board.
- Engines like Stockfish discover zwischenzugs instantly, but they remain a favorite theme in human tactical puzzles because they subvert natural move order instincts.