The pawn breakthrough — a sacrifice tears the path open

White wins White to move · Pawn endgames · Difficulty about Elo 1500

The plan

Two white pawns face a single black one and still cannot advance a single step: the one black pawn covers both squares they want to move to, and captures whichever one tries. That is exactly the situation in which the breakthrough is born. White sacrifices the pawn that the enemy king could still reach, and so forces the black pawn to leave its post — it has to capture, after all, and capturing means changing files. At that same moment the second white pawn is free and runs; the black king stands one file too far away and can no longer get into the square. The pawn that captured also runs, but it starts a whole move later, and in this kind of race one move is everything. The new queen then catches it with check. Whoever sacrifices the wrong pawn instead, or brings the king up first, is left with only a draw.

Rule of thumb: if a pawn blocks two of your own, sacrifice the one that is closer to the enemy king — the other one gets through.

Why this level: The sacrifice pattern that tears the path open

The solution, move by move

1. 1. c6 The ONLY winning move: nine other moves give up the point. The pawn puts itself in front of the black pawn of its own accord, so that it gets captured. The point is not the pawn but the FILE it changes in the process. The pawn sacrificed is the one on the side where the black king stands — the other way round wins nothing (first sideline).
   Sideline 1. a6 The same sacrifice, only on the wrong side. It works exactly the same technically — the black pawn has to capture and changes file in doing so. 1… bxa6 He really MUST capture — here that is even the only move that holds. But now the wrong pawn runs: the one standing on the side of the black king. 2. Kf3 Kd5 3. Ke3 Kxc5 So the black king simply picks it up at leisure, while White in turn has to chase after the pawn he was given. 4. Kd3 Kb4 5. Kc2 a5 6. Kb2 The white king only just catches it: a draw. The breakthrough idea was right, the sacrifice stood on the wrong file.
   Sideline 1. Kf3 The patient move: bring your own king up first, then break through. Only the opponent has a king too. 1… Kd7 And it goes straight to where it has to. From here on the breakthrough is worthless. 2. c6+ The same move as in the main line, only a move later — and so wasted. 2… bxc6 3. a6 The pawn runs again, but this time the black king stands inside the square. 3… Kc7 4. a7 Kb7 The only move, and it is enough: the pawn is stopped on the last square. A draw. A breakthrough pays off for exactly as long as the enemy king is too far away.
2. 1… bxc6 Declining doesn't help: the pawn would otherwise stand on the seventh rank. But by capturing, the pawn no longer covers the square it was guarding a moment ago.
   Sideline 1… Kd6 The sacrifice is declined — the king hurries over instead. 2. cxb7 Then White simply captures, and the pawn stands on the seventh rank. That is the only winning move here. 2… Kc7 3. a6 And again the only one: it is not the pawn on the seventh rank that moves, but the one behind it. It now covers the square the other stands on — which makes the front pawn uncapturable and ties the black king to it. 3… Kb8 4. Kf3 White is in no hurry: the black king cannot leave, and the white one strolls over at leisure. So declining loses too. 4… Kc7 5. Ke4
3. 2. a6 And there it runs. It takes two moves to promotion; the black king needs four from where he stands — he was never in the square, as long as only the black pawn covered the path.
4. 2… c5 The counter-race. It is the only chance and hopeless all the same: Black is a full move behind.
5. 3. a7
6. 3… c4
7. 4. a8=Q
8. 4… c3
9. 5. Qc6+ Check on the file of the running pawn — both at once. That is the standard technique against a pawn on the seventh rank: check on its file first, then capture.
10. 5… Ke5
11. 6. Qxc3+ The pawn falls with check. Queen against bare king, and all of it because of a single pawn sacrifice.

More in Pawn endgames

• The protected passed pawn — the fetter White wins
• The distant passed pawn — the decoy White wins
• The active king outweighs a pawn Draw
• Wing majority 3 against 2 — the candidate first White wins
• Corresponding squares (Lasker-Reichhelm 1901) White wins
• One pawn holds two — the saving trade Draw