# Mate in 2 from "The soviet Chess Primer" but wrong

I found this exercise on page 51 of the "The soviet chess primer" and I think there is a mistake. Chess.com analysis says there is a mate in 13 moves.

I'm correct thinking there is a mistake? Or am I missing something?

``````5Kbk/6pp/6P1/8/7R/8/8/8 w - - 0 1

``````

Edit: here the solution that the engine didn't find:

``````1. Rh6 gxh6 2. g7#
``````
• White to play or black to play? I suspect the former ... Commented Dec 9, 2023 at 18:19
• @IanBush OP posted the FEN `5Kbk/6pp/6P1/8/7R/8/8/8 w - - 0 1` which is White to move. I find it very unlikely that an engine missed this mate in 2. Lichess' web-based Stockfish finds it immediately running on 12 year old hardware. Commented Dec 10, 2023 at 1:27
• @SecretAgentMan That's why I am asking. I also can't believe any engine from the last 10 years or more missed this. Commented Dec 10, 2023 at 8:31

On the assumption that the problem is a #2, white to move (which might be entirely wrong), you are missing something.

Forget about white for the moment, but consider what black's options are if it was black to move. Mainly Bishop moves, and as those drop the guard of h7, Black will be mated in the following move (with one exception)

Now go back to white to move: is there any white move that will retain that situation (i.e. that black's move will lose), and take away that single exception, without producing any other advantage for Black? Once you know how black can escape a #2 when black moves, it should not be difficult.

In the chess problem workd, this is known as a block position, and it is a kind of judo chess problem.

Many, perhaps most, chess playing engines struggle with these types of positions.

(Edit: Doesn't the book have solutions?)

• I see white can do a “waiting move” but black can do mi e the pawn to h6 and there is no mate Commented Dec 9, 2023 at 19:41
• @Ignazio So whatever white waiting move you should consider must also prevent 1. ... h6.
– user30536
Commented Dec 9, 2023 at 19:55

Checking a chess analysis board myself, there is a mate in thirteen with black to move. It is very likely that this is what you set up on chess.com.

The puzzle was certainly intended with white to move. Try again to find the mate in two with white moving first, yourself. And, if you do want to use the computer again, make sure you set it up correctly with which side has the move.

• White to move. And chess.com seems to be configured correctl Commented Dec 9, 2023 at 19:44