Lone Pawn in Rook Endings: Number of Files Needed to Cut the King Off (Part 2)

I have written about a particular type of rook ending where the attacker has a lone central or bishop passed pawn while the defender's king is cut off last week. If you have not seen it, please click here to check it out. In part 2 of this mini-series, I will focus on knight and rook pawns. Without further ado, let's get started!

Recall that when the lone bishop or central pawn has not advanced beyond the fourth rank in a rook endgame, the defender's king must be cut off by two files for the position to be won. An example of such a scenario can be seen below.

Knight pawn

Let's consider what happens if all the pieces were shifted one file to the queenside (left). Is the position still winning for white? (Hint: try to visualise white deploying the same winning technique demonstrated in part 1. Does the lack of space on the queenside or the extra space on the kingside change anything?)

1. The white king must leave his pawn shelter and head towards the enemy rook
2. After a series of checks from the black rook, white wants his king to be two squares away diagonally from his pawn. In this case, that would be d6 (assuming there is no ...Rd8+ skewer) or '-a6'.
3. Finally, he would want to meet ...Rb8 with Rb1.

Since the second step cannot be completed, black secures a draw in that position.

What happens if the black king is cut off by three files? The win becomes so trivial that it is almost not worth explaining.

Rook pawn

Finally, we can look at rook pawns. I have kept this scenario for the end of this mini-series because the rook pawn has several unique properties, making its rook ending more complex than those of other pawns. First of all, the defender has the option, in many more positions, to trade rooks into a drawn king and pawn ending. Additionally, when the attacker's king moves in front of his pawn, the enemy rook can sit on the adjacent file, trapping the king.

In fact, in the following position, despite being cut off by three files, black can hold the draw very comfortably. He just needs to ensure that his king controls the d8 square for as long as the white rook remains on the d-file.

As it can be seen from the fifth move, white is one move too slow. He needs to cut the king off by four files to win. Even then, the win involves many lengthy variations. For this reason, some players may choose to memorise the technique rather than having to work out the moves over the board during their games.

Keeping this in mind, we will return to the position with the pawn on the fourth rank.

Again, black draws the game very easily. There are simply too many ways he can go about obtaining his half point. I believe the easiest of which is to break the white rook's barrier by offering a rook trade on d8. This plan will enable black’s king to inch towards white’s pawn.

1.  Winning chances increase when the pawn has moved further up the board and
2.  Drawing chances increase when the pawn is nearer to the flank

I hope that you enjoyed this article. Take care