King + Pawn vs King · Ending 2
Opposition is the decisive idea when a pawn nears promotion. This chapter explores when the pawn wins, when the defender holds, and how king manoeuvres around the 6th rank decide the result.
The first important position to fix in our minds occurs when the pawn has reached the 6th rank and is only two steps away from promotion. Despite the proximity of the 8th rank, we still need to examine the key details.
Position 1.4 · Pawn on the 6th rank · White to move
FEN: 3k4/8/5PK1/8/8/8/8/8 w - - 0 1
In this position, the pawn can take its last two steps almost automatically because the white king controls the key squares. The black king on g8 cannot reach the promotion square f8 in time to stop the pawn.
Main line
The result changes completely if it is Black to move in Position 1.4. The reason is that the pawn cannot promote if both kings are opposed when the pawn reaches the 7th rank.
Black to move
Position 1.5 · Opposition after …Kg8 · White to move
FEN: 6k1/8/5PK1/8/8/8/8/8 w - - 0 1
Now the kings are opposed. In this kind of position, the side that has the opposition normally has the advantage, and the side to move is at a disadvantage.
Main line
Other moves do not win against accurate defence. For example:
Variation
The stronger side must not push the pawn too quickly.
The pawn should only reach the 6th rank when:
Before pushing the pawn, always ask:
Who will have the opposition after the pawn advances?
When the pawn is already on the 6th rank, king manoeuvres driven by opposition decide the result. Taking the opposition first is usually the winning method.
Position 1.6 · Taking the opposition on the 6th rank · White to move
FEN: k7/8/2P5/K7/8/8/8/8 w - - 0 1
White to move. The white king on a5 and the black king on a8 are on the same file with two squares between them. White takes the opposition.
Winning move
White takes the opposition.
Main line
Side line: 2…Ka8
If 2…Ka8, Black tries to induce a mistake near the edge.
Correct
Most mistakes in King + Pawn vs. King endings occur in positions like this. The situation is provisional: the black king cannot keep the opposition because the pawn controls the f7-square.
Position 1.7 · Losing the opposition · White to move
FEN: 8/6k1/4P3/6K1/8/8/8/8 w - - 0 1
The best squares for the lone king are normally those in front of the pawn. If the king cannot reach them in the right circumstances, the defence collapses.
Winning move
Now, wherever the black king moves, he loses the opposition.
Main line
Variation
Not all pawns work the same. As pawns approach the edge of the board, they often have their own special rules. The rook’s pawn is the most exceptional, but the knight’s pawn also has specific stalemate details because of the nearby edge.
Position 1.8 · Knight’s pawn stalemate resource · White to move
FEN: 8/8/8/8/8/5kp1/7K/8 w - - 0 1
Use this position as a preview or transition to the next lesson. The knight’s pawn on g3 and the nearby edge create stalemate possibilities that do not arise with centre pawns.