Reserve tempo - chess term
Reserve tempo
Definition
A reserve tempo (also called a “spare move” or “tempi in hand”) is a move you can play that does not materially change the position, allowing you to “waste” time and pass the move to your opponent. In endgames—especially king-and-pawn endings—having a reserve tempo is often the difference between winning, drawing, or losing, because it lets you choose when the opposition or a zugzwang position occurs.
How it’s used in chess
- Endgames: You use reserve tempi (typically with pawn moves like a2–a3 or h2–h3) to hand the move to your opponent at a key moment, forcing zugzwang.
- Parity control: A pawn on its starting square can often move one or two squares, letting you adjust the move count (parity) to engineer a favorable turn order.
- Waiting moves: Sometimes a move like h3 or a3 in the middlegame serves as a flexible “waiting” resource; while not usually called a reserve tempo in openings, the idea is similar.
- Triangulation: With kings or pieces (e.g., rooks), you can “lose a move” by taking a triangular route, functionally creating a reserve tempo without using pawns.
Strategic significance
In basic pawn endings, opposition alone is not enough; you also need reserve tempi to control who moves when the kings confront each other. Rook pawns on their starting ranks are especially valuable because you can choose between a one-step (a2–a3) or two-step (a2–a4) advance to fine-tune parity. Classic manuals (Philidor, Fine) and modern endgame texts (e.g., Dvoretsky) repeatedly stress that counting spare pawn moves on each wing is critical to accurate evaluation.
Typical sources of reserve tempi
- Pawns on their initial rank (a2, b2, …, h2 for White; a7, …, h7 for Black) that can advance one or two squares.
- Rook pawns (a- and h-pawns), whose early moves often do not affect central/key squares, making them ideal waiting moves.
- Locked or fixed pawn structures where a non-critical pawn can advance without changing the essential features of the position.
- Piece triangulation (king or rook) to deliberately lose a move when pawns cannot safely advance.
Example 1: Gaining the opposition with a reserve pawn move
Position: White king e4; pawns a2, h2. Black king e6; pawns a7, h7. White to move. White lacks the opposition, but has a reserve tempo with a pawn move. After 1. a3, Black must move the king, and White then seizes the opposition with 1... Kf6 2. Kf4 or 1... Ke6 2. Ke4.
Illustrative line: 1. a3 Kf6 2. Kf4 Ke6 3. Ke4. White has engineered the opposition and dictates the next king confrontation.
Example 2: Using the two-step option to fix parity
Position: White king d4; pawns a2, h2. Black king d6; pawns a6, h6. White to move. If White plays 1. a3? and 2. h3?, Black mirrors with …a5 and …h5, keeping pace. Instead, 1. a4! uses the two-step choice to change parity: after 1… h5 2. h4, Black has no pawn moves left and must yield a king move, falling into zugzwang.
Illustrative line: 1. a4 h5 2. h4 Ke6 3. Ke4. Black was forced to move the king; White takes the opposition and can outflank.
Practical tips
- Count spare moves on both wings before simplifying to a pawn ending.
- Prefer keeping a pawn on its initial square if a later parity adjustment might matter.
- Don’t rush with “useful” pawn moves in the middlegame; they might become your reserve tempi in the ending.
- Remember that triangulation with the king or rook can serve as a non-pawn reserve tempo when pawn moves are harmful.
Common pitfalls
- Eliminating your own reserve tempi too early (e.g., automatic h2–h3 or a2–a3) and reaching a lost zugzwang later because you cannot pass the move.
- Miscounting parity: a pawn on its starting square offers a choice of advancing one or two squares once—this is a parity tool, not “two separate spare moves.”
- Using the wrong pawn as a waiting move and inadvertently weakening key squares or creating a target for the opponent’s king.
Interesting facts
- Endgame composers frequently build studies around reserve tempi and zugzwang; whole positions are won solely because one side has a single extra spare move.
- Capablanca’s and Smyslov’s endgame technique often showcased impeccable tempo play, including triangulation and the subtle preservation of spare pawn moves.