6

Reading the first chapters of Jeremy Silman’s endgame book I breezed through the exercises, as I expected. It starts with KRR vs K and KQ vs. R – even half-asleep I can do this reliably against a computer. The next step in the book is mating with a queen against a minor piece and I found KQ vs. KB similarly easy.

However, right after comes KQ vs. KN and here I run into trouble: the computer defends so accurately that I cannot see how to make progress.

Silman’s description leads me to believe it is supposed to be quite easy ("Queen versus Knight is a fairly simple win”) and the topics before and after are very easy, yet against the computer I can often not win within 50 moves (sometimes I am lucky). Sometimes I can break through the wall of checks given by the knight briefly, only to have the opponent’s king escape back to the middle a few moves later.

According to Silman a player rated below 1200 is supposed to be able to do this. What am I missing?

6
  • Easy against a human or a engine? A human opponent won't play perfect moves either.
    – qwr
    Commented Jul 9, 2023 at 15:34
  • 3
    30+ moves is hard to believe, even for distance to mate (as opposed to either mate or safely capturing the Knight). Maybe it's 30+ ply, which is only 15+ moves? Can you give an example of such a position? Commented Jul 9, 2023 at 19:47
  • 1
    @NoamD.Elkies I’m getting a terrible feeling I misinterpreted the numbers on the Syzygy website! syzygy-tables.info/?fen=7Q/8/8/3k4/4n3/8/8/4K3_w_-_-_0_1 The DTM and DTZ numbers are indeed plies, rather than moves! My apologies. That takes care of that argument, however, it changes nothing about the fact that I don’t see how to make progress against the computer in KQ v KN.
    – 11684
    Commented Jul 9, 2023 at 20:43
  • 5
    Can you give an example game? (I already have a hunch in which kind of position you are stuck.) Commented Jul 10, 2023 at 7:08
  • 2
    Your goal is to push the king of the opponent to the edge of the board, and you should use queen and king for that. Maybe you can give an example where you are stuck in a loop and cannot make progress, so we can show you what to do, what the plan would be.
    – d4zed
    Commented Jul 10, 2023 at 7:55

1 Answer 1

3

How easy is Q vs. N supposed to be?

It is sufficiently easy that it is hard to find books showing how it is done.

Comparing with the much more problematic king + rook vs king + knight we see that that is a draw unless the knight is separated from the king when it is possible for the rook and king to hunt down the knight. If the knight is close to the king then it is safe and it can also defend the king from checkmate.

With king + queen, however, the knight is not mobile enough to prevent checkmate. Like king + rook, the knight must stay close to the king to avoid being lost.

So, given that we know what to do, i.e. checkmate the king, the method becomes clear.

The king has first to be driven to the edge of the board. To do that our king is needed to help. Our queen will generally be used a bit like a rook to cut the king off along a rank and our king brought up to a position in opposition. Except that when we drive the king back with our queen we generally do that from one of the squares in front of the king because our queen can also move like a bishop as well as a rook.

If the knight checks from next to the king when we are in opposition to the king then we will move our king 2 squares diagonally opposite the knight (diagonal opposition to the knight) and prepare to check with our queen on the square between our king and the opposing knight.

Here is an example taken from that old classic, Reuben Fine's Basic Chess Endings:

[Title "KQ vs KN"]
[fen "8/8/3nk3/8/8/8/8/KQ6 w - - 0 1"]

1. Kb2 {first bring the king up} Kd5 2. Kc3 Ne4+ 3. Kd3 Nc5+ 4. Ke3 {First diagonal opposition to the knight} Ne6 5. Qf5+ {driving the king back} Kd6 6. Ke4 {king up} Nc5+ 7. Kd4 Ne6+ 8. Kc4 {diagonal opposition to the knight again} Nc7 9. Qc5+ {drive the king back again} Kd7 10. Qb6 {cut the king off} Ne6 11. Kd5 Nc7+ 12. Ke5 Ne8 13. Qe6+ Kd8 14. Qf7 Nc7 15. Kd6 Nb5+ 16. Kc5 Nc7 17. Kc6

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.