ChessWorld Hitchhiker's Guide to Chess

Scope: This glossary does not intend to cover player names, opening names, or Composition terms. The Glossary aims to relate the terms to ChessWorld where possible when giving examples.
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Glossary Course Modules with Tactical Puzzle Examples

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Z

Zugzwang
An position in which the side to move stands to lose or gain a considerable disadvantage by making a legal move. Zugzwangs most often occur in the endgame phase of the game where there is reduced material and therefore less possibilities. A very simple and very clear cut zugzwang example is shown below:-








Analyse position

Here if Black did not have to make a legal move, then Black could draw. However if it is Black's turn, then the pawn will promote into a queen because Black has to move the king to a legal square which would enable White to queen the pawn. It should also be noted that if was White's turn to move, then again the logical result would be a draw. So Endgames such as this are often decided by the compulsion to move and whos turn it is to move.

There have been some spectacular high level games which have seen a virtual Zugzwang occur in the middlegame. One such spectacular game the following Karpov vs Kasparov game, in which Karpov has to generate counterplay by compromising his position with the move 30.f3 :-

[Click here to replay the game]
Karpov,Anatoly 2590 vs.Kasparov,Garry 2585, 1985 1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 Nc6 5.Nb5 d6 6.c4 Nf6 7.N1c3 a6 8.Na3 d5 9.cxd5 exd5 10.exd5 Nb4 11.Be2 Bc5 12.O-O O-O 13.Bf3 Bf5 14.Bg5 Re8 15.Qd2 b5 16.Rad1 Nd3 17.Nab1 h6 18.Bh4 b4 19.Na4 Bd6 20.Bg3 Rc8 21.b3 g5 22.Bxd6 Qxd6 23.g3 Nd7 24.Bg2 Qf6 25.a3 a5 26.axb4 axb4 27.Qa2 Bg6 28.d6 g4 29.Qd2 Kg7 30.f3 Qxd6 31.fxg4 Qd4+ 32.Kh1 Nf6 33.Rf4 Ne4 34.Qxd3 Nf2+ 35.Rxf2 Bxd3 36.Rfd2 Qe3 37.Rxd3 Rc1 38.Nb2 Qf2 39.Nd2 Rxd1+ 40.Nxd1 Re1+ 0-1
A classic example of middlegame Zugzwang also occured in the following very famous Nimzovich game:- Saemich vs Nimzovich in which Nimzovich despite being material down, completely removed all counterplay from the opponent, to such an extent that any legal move would start losing material and the game.

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Zwischenzug
A move played in response to a capture which is not a recapture, but which forces the opponent to make a reply which cannot avoid eventual capture. Most Zwischenzugs are checks. An example is shown below:-








Analyse position

Black has just captured White's pawn on d4. Now White should try and restore material balance by playing either Nxd4 or Qxd4. However White can also throw in an intermediate check, by playing Bb5+ as shown below:-







Analyse position

Then when Black does something about the check such as Nc6, White can then recapture the pawn.







Analyse position

In this example, the Intermediate move does not cause Black too much trouble, but there are situations possible where the Zwischenzug can lead to a big advantage.

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