Wednesday, September 05, 2007

Chekhover, 1938

Vitaly Chekhover was a master on knight endings. He once wrote an entire book on the subject with the help of Yuri Averbakh.

Black to move
. In this composition, immediately pushing the f- or h-pawns obviously leads to failure. What's less obvious is that the king cannot travel to the kingside to help his pawns.

  1...Kc3 2.Ne4+! {forks the king and f-pawn} =
  1...Kc5 2.Ne4+! {forks the king and f-pawn} =
  1...Kc4 2.Ne4! {threatens Nxf6} f5 3.Nd6+! =

Since the c3, c4, and c5 squares are mined, Black must find another path to the kingside pawns if he wishes to win. Kb3 and Kb5 are tempting.

If 1...Kb3, White has a brilliant refutation:   2.Ne4! f5 3.Ng3! f4 4.Ne2! f3 5.Nd4+! =. I suggest playing these moves out. Once you've seen the solution, I think you'll find it's more intuitive than the long list of moves suggests.

If 1.Kb5 then Ne4! 2.f5 Nd6+! =

What does that leave? Well, there's the counter-intuitive Ka5-Kb6 maneuver. Black could then cross the c-file on c6, c7, or c8. Let's play forward a few moves and reach that position: 1... Ka5 2. Ka2 Kb6 3. Kxa3.

3...Kc6 2.Ne4! f5 3.Ng3! f4 4.Ne2! f3 5.Nd4+! Yes, it's the same brilliant maneuver that White used in answer to Kc4.

3...Kc7 4.Nh5! f5 5.Ng7! f4 6.Ne6+! In a similar manner, White again wins the f-pawn. So no matter what, White can draw using knight forks!

If the king were on c8, then 4.Ne4 f5 5.Nd6+! would win.

We've already seen how White can draw using tactical shots, but let's consider what would happen if we missed one so 3...Kc7 4.Kb4 Kd7 5.Nf5 h5:

White's knight creates a barrier that the Black king can't penetrate. Black made progress with his h-pawn, but now he's forced back the way he came.


White's king increases the size of the barrier. How can Black make progress? If 6...Kc7 7.Ng7! h4 8.Ne8+! All other moves result in the loss of the queenside pawn. So now we've seen how useful creating barriers in knight endings can be, and how easily they can be setup.

I hope you enjoyed this wonderfully instructive composition from Chekhover. The missed-tactic game is below in PGN format, for your convenience.

[Event "Chekhover, 1938"]
[Result "1/2-1/2"]
[SetUp "1"]
[FEN "8/8/p4p1p/8/1k6/p5N1/8/K7 b - - 0 1"]
[PlyCount "32"]

1... Ka5 2. Ka2 Kb6 3. Kxa3 Kc7 4. Kb4 Kd7 5. Nf5 h5 6. Kc5 Kd8
7. Kb6 Kd7 8. Kxa6 Kc6 9. Nh4 Kd6 10. Kb6 Ke5 11. Kc5 Ke4 12. Kc4 f5
13. Kc3 f4 14. Kd2 f3 15. Ke1 Ke3 16. Nxf3 Kxf3 17. Kf1 1/2-1/2


transformation said...


likesforests said...

Thanks. I'm learning endings one endgame at a time. Perhaps in a decade I'll be good at them. ;)