Zwischenzug (in-between move) in chess

Zwischenzug: what is it

A zwischenzug (German Zwischenzug, "in-between move") is an unexpected move that is inserted between two "obvious" moves of a line. Most often it comes between a capture and the recapture.

The opponent expects you to take back or play "by the script", but first you give a check, make a capture or create a strong threat. Only then do you return to the planned move. Very often a zwischenzug changes the evaluation of the whole line.

Why a zwischenzug is dangerous

When we calculate variations, we usually think "they take, I take back". A zwischenzug breaks this habit: instead of recapturing, the opponent inserts a check or another threat, gaining time and often material.

Important: a zwischenzug only works if it is stronger than the "normal" continuation. It must be a move the opponent has to respond to: a check, a capture of a valuable piece or a mate threat.

Three types of in-between moves

  • With check. The most common type. A check is inserted between captures: the opponent has to deal with it first, and in the meantime you improve your position or win back material.
  • With a capture. You are in no hurry to take back or accept a loss: first you capture an enemy piece yourself. This often lets you restore the material balance.
  • With a threat. A quiet move that creates such a strong threat (mate, trapping a piece, a second strike) that the opponent has to turn away from the planned capture.

How to find an in-between move

  1. When an "automatic" capture appears in a line, stop and ask yourself: "Do I really have to take right now?"
  2. Find the most forcing moves in the position: checks, captures, direct threats.
  3. Check whether one of them is a move the opponent has to deal with before the trade is "closed".
  4. Make sure that afterwards you can still make the planned capture, and work out how much your position or material has improved.

Tips to spot an in-between move faster

For kids

Imagine you have a "secret step". Your opponent thinks the game will go as usual: "they take, I take", but suddenly you insert a check or another capture. Your opponent is confused, and you have already won a piece.

Before you "automatically" take back, look: do you have an even stronger move right now?

For adults

When calculating, mark all the forcing replies in every branch. It is especially useful to look for in-between moves in tactically rich positions: an exposed king, hanging pieces, open lines.

Typical motifs: a sacrifice on a key square + a check that gains a tempo, a trade with a capture inserted "along the way", a quiet move with two threats.

Examples

Try it yourself: make a move on the board. If you get stuck, press "Show solution".

1. An in-between move with check

Idea: Black has just played 1...Rxd2, taking the knight on d2, and expects the "normal" recapture Bxd2. But the rook has left d8, and now the rook on f8 attacks the queen on a8: on 2.Bxd2? comes 2...Rxa8. On the other hand, the queen on a8 also attacks the rook on f8 along the eighth rank, so a check can be inserted between the captures.

2.Qxf8+! - an in-between move with check. The king cannot take the queen and steps away (2...Kh7), and only then does White play 3.Bxd2, winning back the knight. The result: material is not just restored, White has won a rook.

Solution: 3.Bxd2 - only now does White win back the knight. The result: the rook on f8 has been won as well.

2. An in-between move with a capture

Idea: White has just played 1.bxa5, catching the queen with a pawn, and expects Black to accept the loss. But the queen on d4 is attacked by the rook on d8, so a capture can be inserted before the trade is "closed".

1...Rxd4! - an in-between move with a capture. Black takes the white queen themselves. The bishop on f3 is on the wrong color, and there is nothing to win back the rook on d4 with: material is restored, and Black has an active rook in the center.

Solution: 1...Rxd4! - Black takes the queen in return. White has nothing to win back the rook on d4 with (the bishop on f3 is on the other color): material is restored, and Black has an active rook in the center.

3. An in-between move with a threat

Idea: the white rook on b6 is aiming at the knight on b8, and the white knight on d2 is unprotected. It is "natural" to take it right away with 1...Rxd2, but after 2.Rxb8 material is equal again. Black has something much stronger: an in-between quiet move with a threat.

1...Nd7! - the knight steps out of the attack and attacks the rook on b6 itself. White has to spend a move saving the rook (for example, 2.Rc6), and only after that 2...Rxd2: Black has won a piece.

Solution: 2...Rxd2 - only now does Black take the knight. An in-between move with a threat, and Black is a piece up.