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pappaapsu
10-08-2007, 07:29 AM
Is there a possible outcome besides stalemate?

Spiny Norman
10-08-2007, 08:06 AM
Saw your shout and replied there ... but some the possible outcomes are:

Draw:
* draw by agreement
* draw by repetition of moves
* draw by stalemate
* draw by 50 moves made without a capture or a pawn move
etc

Of course, you could hope for your opponent's mobile phone to ring, thereby giving you a win. ;)

Kevin Bonham
10-08-2007, 02:48 PM
Saw your shout and replied there ... but some the possible outcomes are:

Draw:
* draw by agreement
* draw by repetition of moves
* draw by stalemate
* draw by 50 moves made without a capture or a pawn move
etc

Of course, you could hope for your opponent's mobile phone to ring, thereby giving you a win. ;)

Actually the instant king and bishop versus king appears on the board the game is drawn immediately under Article 9.6 so none of the above things have time to occur - except that it could also be a draw by stalemate if the move producing K+B vs K also stalemated the player with the lone K.

Technically it is a draw by dead position. Sometimes also called "insufficient mating material" although they are not always the same thing.

An arbiter who sees this endgame in progress must stop the game and declare a draw immediately.

pappaapsu
11-08-2007, 06:32 AM
Very useful responses. Thank you much. Are there other end game piece combinations which would result in a draw automatically? I would have to play with trial and error to find out which pieces could not mate a lone king.:wall:

DanielBell
11-08-2007, 06:57 AM
Very useful responses. Thank you much. Are there other end game piece combinations which would result in a draw automatically? I would have to play with trial and error to find out which pieces could not mate a lone king.:wall:

King + knight cant mate I know that much! :D

Kevin Bonham
11-08-2007, 03:01 PM
Very useful responses. Thank you much. Are there other end game piece combinations which would result in a draw automatically?

King and knight versus king
King and bishop versus king and bishop if the two bishops are on the same colour squares
King versus king of course!

I think those are the only piece combinations which result in an automatic draw no matter where the pieces are placed. But an automatic draw can also result with different pieces on the board if they are arranged in such a way that checkmate is never possible for either side no matter what moves are played

For instance White king e1, white pawns b4,e4,h4, Black king e8, black pawns b5,e5,h5 is an automatic draw the instant it appears because all pawns are blocked and the kings can't get through so neither side can possibly checkmate from this position with any series of legal moves.

EGOR
13-08-2007, 10:38 AM
I would have thought that King vs King and two knights would be an automatic draw as well?

Spiny Norman
13-08-2007, 02:20 PM
Funnily enough I was "assistant arbiter" at the Billanook junior tournament on Saturday. There were 39 boards in operation, so in the initial flurry of activity each round it got pretty hectic (we had about 4 "assistant arbiters" working out the basic issues, with knotty problems referred to the chief arbiter for a decision).

A N Y W A Y ... as it turned out, one board landed up in K+B vs K endgame and they were banging moves out at a furious pace. I went over and gently intervened, showing them why it was a draw.

But I also did see one game that had just K vs K on the board, and they were still playing on for a while before the penny dropped ... :)

Capablanca-Fan
13-08-2007, 05:01 PM
I would have thought that King vs King and two knights would be an automatic draw as well?
No, because there is a possible mate if the defender displays "unskilled counterplay". This means that if the inferior side's flag fell, he would lose:


6.10 Except where Articles 5.1 or one of the Articles 5.2 (a), (b) and (c) apply, if a player does not complete the prescribed number of moves in the allotted time, the game is lost by the player. However, the game is drawn, if the position is such that the opponent cannot checkmate the player`s king by any possible series of legal moves, even with the most unskilled counterplay.

But KB mentioned in another thread that IA Gijssen thought that a GM playing on v a GM should be warned that he was violating:


12.1 The players shall take no action that will bring the game of chess into disrepute.

In a quckplay finish, after a few moves, the arbiter should probably step in and apply:


10.2 a: If the arbiter agrees the opponent is making no effort to win the game by normal means, or that it is not possible to win by normal means, then he shall declare the game drawn.

Kevin Bonham
13-08-2007, 06:46 PM
In a quckplay finish, after a few moves, the arbiter should probably step in and apply:


10.2 a: If the arbiter agrees the opponent is making no effort to win the game by normal means, or that it is not possible to win by normal means, then he shall declare the game drawn.

The arbiter can only apply 10.2a following a claim by a player with <2 minutes on their clock. However I would uphold the claim immediately if the game involved players of even reasonable club standard.

EGOR
13-08-2007, 07:44 PM
No, because there is a possible mate if the defender displays "unskilled counterplay".
Really, I didn't realise it was even possible?

Kevin Bonham
13-08-2007, 11:22 PM
Really, I didn't realise it was even possible?

1.Nf6+ Kh8?? 2.Ng6#

EGOR
14-08-2007, 11:17 AM
Thank you for that KB, I've learned something.

Capablanca-Fan
14-08-2007, 04:38 PM
Note that KNN v KP can be a win sometimes. And even in theoretically drawn positions, none other than Karpov has gone wrong. So an arbiter should allow the N side to play on if the pawn is safely blockaded.

The Wikipedia article http://en.wikipedia.org/wiki/Two_knights_endgame seems not bad for a change, and it links to the excellent articles by GM Karsten M&#252;ller.