The usual way to win KNN vs KP (if possible, depens on the position of the pieces especially the pawn) is to block the pawn with one knight and force the king to an edge with the other one and the king. Later get the knight blocking the pawn to that edge and mate the king. I would never win this in a real game. Has anyone ever had such an end game? I can’t remember ever having seen this in practice.
In this case it is a bit easier as the king is already in the corner and the important pawn blockade on a7 gives white time to build up the prison before the king can escape.
1. Na6+, Ka8 2. Nc5! and black can do nothing against Nc6 and his king is prisoned after which white can simply get in his king to take away the b7 protection exercise from the c5 knight and mate with this knight, that is Kb8 3. Nc6+, Ka8 4. Kc8, a6 5. Nxa6 oups… 5. Ne6, a5 6. Nc7# (or Nc5-d7-b6#) or if 2. -, a6/a5 3. Nc6 4. Kc8 and so on.
My dad had KNN vs KP in a real game once, but that is the only case I have seen. The game was adjourned after move 40 (with some more pieces on the board) and prepared himself well for the endgame. Around move 50 his opponent exchanged some pieces and wanted to claim a draw because KNN vs K cannot win. “Not with the pawn” he replied, and he managed to win the game!
PdV: Thanks for the report. As it seems your father was really lucky that it was an adjourned game so he could well prepare for this very special end game. But very good job by him that he managed the win which should be still hard enough even with preparation.
His opponent surely was very surprised as it seems he did not know that this end game was (theoretically) won. Or was it just a try by him hoping your father agreed the draw? 🙂
Would be interesting to see if many good GMs would be able to win this end game without direct preparation. Susan, do you know the technique? 🙂
Sorry for offtopic but this interested me, so thanks for the answer once more.
Best wishes Jochen
PS: And ontopic: Ano 4:32, good add. I didn’t even try Nce6 as I directly tried to keep the black king as imprisoned as possible and Na6 seemed to do this job best. 1. Nce6, a5/a6 2. Nc5 [threat of Nc6+], Ka7 3. Kc7 and he stays in there, too. (What I like best about this line is that the rest of the solution seems to be dual free while in the Na6 line there are several ways for white to proceed: Here it is Nce6, a5 2. Nc5 (only move), Ka7 3. Kc7 (only move), a4 4. Nc6+ (only move), Ka8 5. Nd7 (only move; Nxa4?/Nd5 6. Nc7??) or even cuter 1. -, a6 and 5. Na4? fails to stalemate. :-))
Jochen, indeed he was lucky that it was an adjourned game, and if I remember correctly (it was some years ago) his opponent even missed a chance to draw somewhere. I am not sure whether his opponent was bluffing, or that he really thought that it was a draw.
In any case, it seems he was trying to reach the double knights ending; although it might be theoretically won, it is not always easy to do so. The defending king was near the edge of the board, but not in the corner yet!
A.Weiler’s 2.Nb4 indeed seems to work as well! The funny thing is that it might result in the same final position (pawn on a4, Kc8, Nc7, Nc6) but in the meantime the knights have traded places!
@Jochen: This ending also occurred in Wang Yue-Anand, Amber tournament 2009. Anand was unable to win with the two knights (one should mention that this was a blindfold game!).
1.Na6 Ka8 2.Nc5 a5 (2…Kb8 3.Nc6 Ka8 4.Kc7 a5 5.Nd7 a4 6.Nb6#)
3.Kc7 a4 4.Nc6 a3 5.Nd7 a2 6.Nb6#
(not all the lines, but the rest works similar).
Kind regards,
PdV
Looks quite forced.
The usual way to win KNN vs KP (if possible, depens on the position of the pieces especially the pawn) is to block the pawn with one knight and force the king to an edge with the other one and the king. Later get the knight blocking the pawn to that edge and mate the king.
I would never win this in a real game. Has anyone ever had such an end game? I can’t remember ever having seen this in practice.
In this case it is a bit easier as the king is already in the corner and the important pawn blockade on a7 gives white time to build up the prison before the king can escape.
1. Na6+, Ka8 2. Nc5! and black can do nothing against Nc6 and his king is prisoned after which white can simply get in his king to take away the b7 protection exercise from the c5 knight and mate with this knight, that is
Kb8 3. Nc6+, Ka8 4. Kc8, a6 5. Nxa6 oups… 5. Ne6, a5 6. Nc7# (or Nc5-d7-b6#)
or if 2. -, a6/a5 3. Nc6 4. Kc8 and so on.
Best wishes
Jochen
Please, easier puzzle. This is too hard for me.
1. Na6 Ka8
2. Nb4 a5
3. Nc6 a4
4. Kc8 a3
5. Ne6 a2
6. Nc7#
not too late for Susan’s US Open picks. I say Andy Murray and Elena Dementieva.
This is a tough one.
I would try to reach the following position
white knights in a6 and b6, white king in c6
black pawn in a7 and black king in a8
1.Nce6 also mates in six.
1.Na6+ Ka8
2.Nc5 blk any
3.Nc6 blk any
4.Kc8 blk any
5.Na6/e6 blk any
6.Nc7++
h
@Jochen,
My dad had KNN vs KP in a real game once, but that is the only case I have seen. The game was adjourned after move 40 (with some more pieces on the board) and prepared himself well for the endgame.
Around move 50 his opponent exchanged some pieces and wanted to claim a draw because KNN vs K cannot win. “Not with the pawn” he replied, and he managed to win the game!
Kind regards,
PdV
PdV: Thanks for the report. As it seems your father was really lucky that it was an adjourned game so he could well prepare for this very special end game. But very good job by him that he managed the win which should be still hard enough even with preparation.
His opponent surely was very surprised as it seems he did not know that this end game was (theoretically) won. Or was it just a try by him hoping your father agreed the draw? 🙂
Would be interesting to see if many good GMs would be able to win this end game without direct preparation.
Susan, do you know the technique? 🙂
Sorry for offtopic but this interested me, so thanks for the answer once more.
Best wishes
Jochen
PS: And ontopic: Ano 4:32, good add. I didn’t even try Nce6 as I directly tried to keep the black king as imprisoned as possible and Na6 seemed to do this job best.
1. Nce6, a5/a6 2. Nc5 [threat of Nc6+], Ka7 3. Kc7 and he stays in there, too. (What I like best about this line is that the rest of the solution seems to be dual free while in the Na6 line there are several ways for white to proceed: Here it is Nce6, a5
2. Nc5 (only move), Ka7 3. Kc7 (only move), a4 4. Nc6+ (only move), Ka8 5. Nd7 (only move; Nxa4?/Nd5 6. Nc7??) or even cuter 1. -, a6 and 5. Na4? fails to stalemate. :-))
Na6 + Ka8
Nb4 is also working
Thanks and best wishes
A Weiler
Jochen, indeed he was lucky that it was an adjourned game, and if I remember correctly (it was some years ago) his opponent even missed a chance to draw somewhere. I am not sure whether his opponent was bluffing, or that he really thought that it was a draw.
In any case, it seems he was trying to reach the double knights ending; although it might be theoretically won, it is not always easy to do so. The defending king was near the edge of the board, but not in the corner yet!
A.Weiler’s 2.Nb4 indeed seems to work as well! The funny thing is that it might result in the same final position (pawn on a4, Kc8, Nc7, Nc6) but in the meantime the knights have traded places!
Kind regards,
PdV
@Jochen: This ending also occurred in Wang Yue-Anand, Amber tournament 2009. Anand was unable to win with the two knights (one should mention that this was a blindfold game!).
And comments on the related page at chessgames.com ( http://www.chessgames.com/perl/chessgame?gid=1541026 ) mention other games with this ending.