Quick answer
Reserve Tempo is an endgame technique: promotion race and tempo. Work from the first evidence position for Reserve Tempo, and begin by testing d5.
Begin from d5 in 8/8/3p4/8/8/4P3/3K4/7k b - - 1 1. Count the material, king routes, promotion squares and reserve tempi before applying a theoretical rule. The evidence answer is: Reserve Tempo: calculate both promotion paths and include checks before assuming the faster pawn wins. Candidate line: d5.
In the Reserve Tempo example, notice: side Black; pieces Black pawn d6, White pawn e3, White king d2, Black king h1; legal first moves d5, Kg2, Kh2, Kg1. Do not export this inventory beyond the present example; it is a local observation, not a doctrine.
Material and result question
The first evidence board tests promotion race and tempo; the second board tests promotion race and tempo. Sequence A is direct FEN setup. Sequence B is direct FEN setup. Compare them only after setting both FENs. For glossary entries nearby, open the Chess Wiki plus the Endgames hub. Then compare Material Values with Outside Passed Pawn, Triangulation, Pawn Breakthrough around a stalemate resource.
The two inventories make the distinction concrete. A contains side Black; pieces Black pawn d6, White pawn e3, White king d2, Black king h1; legal first moves d5, Kg2, Kh2, Kg1; B contains side White; pieces Black pawn d6, White pawn e3, Black king h2, White king d1; legal first moves e4, Kc2, Kd2, Ke2, Ke1, Kc1. Compare the side to move before comparing the labels in the context of a theoretical draw with practical tests.
Topic dossier for this page and board pair r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:3K4 | r8:7k / r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:7k | r8:3K4: start with a stalemate resource; then test a theoretical draw with practical tests; keep checking distance behind the passer separate from the bishop's color complex; use the king's route around a pawn chain as the transfer check; and reserve king opposition on the critical file for the exception.
Conversion or defense plan
On the first board, calculate d5 after d5 and write down the opponent's best reply around a stalemate resource. On the second board, calculate e4 after e4 and check a theoretical draw with practical tests. Separate the practical conversion question from the result question; side to move and one checking distance can change the conclusion. In this case the useful condition is king opposition on the critical file.
Key claim: Reserve Tempo is illustrated here by promotion race and tempo; the first concrete test is d5. The board anchor is 8/8/3p4/8/8/4P3/3K4/7k; the example is intentionally narrower than the topic label and should not be generalised without checking the surrounding position..
Practical boundary: To answer “What exact king, pawn, and move-order conditions decide reserve tempo, and how should each side play them?”, compare the recorded setup with e4 and the opponent's reply. The decision is useful only when the stated condition survives that concrete test on board 8/8/3p4/8/8/4P3/7k/3K4. The evidence records No tablebase outcome is asserted by this generated record; verify the exact FEN before publication and the second board signature r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:7k | r8:3K4. The false-positive test is whether checking distance behind the passer appears without the bishop's color complex, so the conclusion is useful only when the stated condition survives that concrete test.
Evidence positions
example-1: promotion race and tempo
Show answer
Reserve Tempo: calculate both promotion paths and include checks before assuming the faster pawn wins. Candidate line: d5.
Why this position is here: Reserve Tempo is represented by promotion race and tempo. This is a direct FEN setup with board anchor 8/8/3p4/8/8/4P3/3K4/7k; no opening history is inferred from the diagram.
FEN: 8/8/3p4/8/8/4P3/3K4/7k b - - 1 1
Question: What is the first concrete decision in this reserve tempo position?
Answer cue: Reserve Tempo: calculate both promotion paths and include checks before assuming the faster pawn wins. Candidate line: d5. The first candidate to test is d5. Replay d5 on board anchor 8/8/3p4/8/8/4P3/3K4/7k and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
example-2: promotion race and tempo
Show answer
Reserve Tempo: calculate both promotion paths and include checks before assuming the faster pawn wins. Candidate line: e4.
Why this position is here: Reserve Tempo is represented by promotion race and tempo. This is a direct FEN setup with board anchor 8/8/3p4/8/8/4P3/7k/3K4; no opening history is inferred from the diagram.
FEN: 8/8/3p4/8/8/4P3/7k/3K4 w - - 2 2
Question: What is the first concrete decision in this reserve tempo position?
Answer cue: Reserve Tempo: calculate both promotion paths and include checks before assuming the faster pawn wins. Candidate line: e4. The first candidate to test is e4. Replay e4 on board anchor 8/8/3p4/8/8/4P3/7k/3K4 and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
example-3: promotion race and tempo
Show answer
Reserve Tempo: calculate both promotion paths and include checks before assuming the faster pawn wins. Candidate line: e5.
Why this position is here: Reserve Tempo is represented by promotion race and tempo. This is a direct FEN setup with board anchor 8/8/3p4/8/4P3/8/8/3K2k1; no opening history is inferred from the diagram.
FEN: 8/8/3p4/8/4P3/8/8/3K2k1 w - - 3 3
Question: What is the first concrete decision in this reserve tempo position?
Answer cue: Reserve Tempo: calculate both promotion paths and include checks before assuming the faster pawn wins. Candidate line: e5. The first candidate to test is e5. Replay e5 on board anchor 8/8/3p4/8/4P3/8/8/3K2k1 and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
Reading the line
Read the first example (id example-1) as a complete record: continuation d5, source tablebase. This is a direct FEN setup with board anchor 8/8/3p4/8/8/4P3/3K4/7k; no opening history is inferred from the diagram. If A does not expose promotion race and tempo, correct the evidence before relying on the prose.
Read the second example (id example-2) separately: continuation e4, source tablebase. Its feature is promotion race and tempo; inventory side White; pieces Black pawn d6, White pawn e3, Black king h2, White king d1; legal first moves e4, Kc2, Kd2, Ke2, Ke1, Kc1. Compare what changes between d5 and e4.
Boundary cases
The main mistake to avoid with Reserve Tempo is applying a remembered endgame rule while ignoring side to move, king placement or an unverified result. In A, the missing condition must be located in r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:3K4 | r8:7k after d5; in B, test it against r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:7k | r8:3K4 after e4.
For Reserve Tempo, the first board's evidence boundary (after d5) is No tablebase outcome is asserted by this generated record; verify the exact FEN before publication. The second board's evidence boundary for Reserve Tempo is No tablebase outcome is asserted by this generated record; verify the exact FEN before publication. If a trusted source or careful calculation changes the conclusion around the king's route around a pawn chain, update both the evidence record and this article.
Practice from a real game
play the position for both sides, record the critical tempo, and verify the exact FEN against the cited tablebase before publication. Start with A's side to move and r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:3K4 | r8:7k; record two candidates, the reply to d5 and the correction. Repeat with B's side to move and r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:7k | r8:3K4; the changed board tests transfer rather than diagram memory.
After the drill, compare your notes with Outside Passed Pawn, Triangulation, Pawn Breakthrough through the bishop's color complex. Keep A's rejected alternative beside B's chosen line e4; this shows whether the conclusion survived a new board signature.
Sources and scope
Sources for Reserve Tempo: Syzygy tablebase verification reference, 1chess.online editorial scope. Source ids are tablebase, original-analysis. Primary evidence hook: tablebase. Comparisons and practice notes are editorial. Evidence revision: 2026-08-remediation-r2.
Scope note for board pair r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:3K4 | r8:7k / r1:8 | r2:8 | r3:3p4 | r4:8 | r5:8 | r6:4P3 | r7:7k | r8:3K4: this page does not claim that d5 is an engine principal variation, that an exact endgame result is verified when the evidence says it is not, or that a tool output replaces human calculation. The conclusion is limited to the recorded boundary and the exception checking distance behind the passer.