You make the call..

Discussion of anything and everything relating to chess playing software and machines.

Moderators: hgm, Rebel, chrisw

As the FIDE TD, how do you arbitrate the result of this game?

Poll ended at Mon Nov 21, 2016 2:17 am

White Wins
1
2%
Black Wins
34
83%
Draw
6
15%
 
Total votes: 41

User avatar
MikeB
Posts: 4889
Joined: Thu Mar 09, 2006 6:34 am
Location: Pen Argyl, Pennsylvania

You make the call..

Post by MikeB »

It seems like we do have a lot of folks who are very knowledgeable about the rules, well here I give you a little quiz and you make the cal! by voting for the right answer as the fictional FIDE TD. I think the group will score over 75% so please don't let me down!

In this exercise , there was no dispute between the players regarding the facts.

In this FIDE game, player White played the move Rxb7. After playing the move, his flag fell , he was not quite quick enough to stop the clock, thus his flag fell.

[d]2n5/kp5R/n7/8/2N5/K1Q5/8/8 w - - 0 1

White claimed he won since the position is a won position for white and he was able to demonstrate that with Gaviota tablebases ;>) , which were loaded on the TD laptop.

Black claimed he won since White ran out of time and that is all that matters.
styx
Posts: 338
Joined: Tue Mar 13, 2012 9:59 pm
Location: Germany

Re: You make the call..

Post by styx »

My approach:

White lost on time: black wins except when he got insufficient material to mate (like in this case) so I voted for "draw".

The big question is: there are positions in which you can mate with 2 knights but not without the opponents help. But if a theoretical chance is sufficient, then black won here. So I am not 100% sure.

The only thing I am pretty sure is: white will never win after hitting the flag. No matter how much material your are up.
User avatar
Graham Banks
Posts: 41423
Joined: Sun Feb 26, 2006 10:52 am
Location: Auckland, NZ

Re: You make the call..

Post by Graham Banks »

Win to black, as it is still possible to mate with two knights with other material on the board.
Highly unlikely of course, but that's the official line.
gbanksnz at gmail.com
Dirt
Posts: 2851
Joined: Wed Mar 08, 2006 10:01 pm
Location: Irvine, CA, USA

Re: You make the call..

Post by Dirt »

Graham Banks wrote:Win to black, as it is still possible to mate with two knights with other material on the board.
I agree.
Deasil is the right way to go.
Colin-G
Posts: 191
Joined: Mon Oct 31, 2016 6:30 pm
Location: England

Re: You make the call..

Post by Colin-G »

Graham Banks wrote:Win to black, as it is still possible to mate with two knights with other material on the board.
Highly unlikely of course, but that's the official line.
I agree, Black wins.

Two knights won against a queen in one of my engine matches last year.
[d]7Q/8/8/8/8/5nn1/5k2/7K w - - 1 89
I was not watching the game being played and just saw the final position.
My first thought was that White had blundered, since how could it have lost with a queen on the board.
After playing back a few moves it was obvious what had happenned.
The queen had only just been promoted from a pawn, which had been forced to move up the rook file, while Black manoeuvred its pieces to give mate without stalemate occuring.
Full game is here
[pgn]
[Event "Arena tournament"]
[Site "MARK8"]
[Date "2015.08.10"]
[Round "2"]
[White "Gaviota 1.0"]
[Black "Chess Tiger 2007"]
[Result "0-1"]
[ECO "B04o"]
[TimeControl "40/300:40/300:40/300"]
[PlyCount "176"]

1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.Nf3 g6 5.Bc4 Nb6 6.Bb3 Bg7 7.Ng5 e6 8.f4 dxe5 9.fxe5 c5 10.O-O O-O 11.dxc5 Qxd1 12.Rxd1 N6d7 13.Ne4 Bxe5 14.Na3 f5 15.Bxe6+ Kg7 16.Nd6 Nxc5 17.Bxc8 Bxd6 18.Rxd6 Rxc8 19.Be3 Ne4 20.Rd3 Kg8 21.h3 Na6 22.Rd4 Re8 23.Re1 Re7 24.Bh6 Nac5 25.g4 Re6 26.Nb5 Rc6 27.b4 Ne6 28.Rd5 Rd8 29.Rxd8+ Nxd8 30.c3 Kf7 31.Rd1 Ke8 32.Rc1 a6 33.Nd4 Rxc3 34.Rxc3 Nxc3 35.gxf5 Nxa2 36.fxg6 hxg6 37.Bd2 Kd7 38.b5 axb5 39.Nxb5 Kc6 40.Nd4+ Kd5 41.Nf3 b5 42.Nh4 b4 43.Bxb4 Nxb4 44.Nxg6 Ke6 45.Kh2 Nf7 46.Nf4+ Kf5 47.Nh5 Nd5 48.Kg3 Kg5 49.Ng7 Kg6 50.Ne6 Nf6 51.Kh4 Ne5 52.Kg3 Nh5+ 53.Kh4 Nf3+ 54.Kg4 Nh2+ 55.Kh4 Nf1 56.Nf8+ Kh6 57.Nd7 Ne3 58.Ne5 Nf5+ 59.Kg4 Nd6 60.Nf3 Nc4 61.Kh4 Nf6 62.Nh2 Kg6 63.Ng4 Ne8 64.Kg3 Ng7 65.Kh2 Nh5 66.h4 Kf5 67.Kh3 Kf4 68.Nf6 Nxf6 69.h5 Ne3 70.h6 Nh7 71.Kh4 Nf5+ 72.Kh5 Ne7 73.Kh4 Ng6+ 74.Kh3 Kf3 75.Kh2 Nf4 76.Kg1 Ke2 77.Kh2 Kf2 78.Kh1 Kg3 79.Kg1 Ng2 80.Kf1 Kf3 81.Kg1 Ne3 82.Kh2 Kg4 83.Kg1 Kg3 84.Kh1 Kf2 85.Kh2 Ng5 86.Kh1 Nf3 87.h7 Nf5 88.h8=Q Ng3# 0-1
[/pgn]
User avatar
Guenther
Posts: 4605
Joined: Wed Oct 01, 2008 6:33 am
Location: Regensburg, Germany
Full name: Guenther Simon

Re: You make the call..

Post by Guenther »

MikeB wrote:
In this FIDE game, player White played the move Rxb7. After playing the move, his flag fell , he was not quite quick enough to stop the clock, thus his flag fell.

2n5/kp5R/n7/8/2N5/K1Q5/8/8 w - - 0 1
The one who voted for a White win after the flag already fell, should hand back his chess license ;-)
elpapa
Posts: 211
Joined: Sun Jan 18, 2009 11:27 pm
Location: Sweden
Full name: Patrik Karlsson

Re: You make the call..

Post by elpapa »

Graham Banks wrote:Win to black, as it is still possible to mate with two knights with other material on the board.
Highly unlikely of course, but that's the official line.
This has got to be the correct answer. I voted black win as well.
User avatar
Evert
Posts: 2929
Joined: Sat Jan 22, 2011 12:42 am
Location: NL

Re: You make the call..

Post by Evert »

MikeB wrote: White claimed he won since the position is a won position for white and he was able to demonstrate that with Gaviota tablebases ;>) , which were loaded on the TD laptop.
Six piece Gaviota tablebases?

Anyway, the flag fell, so white loses the game.
Joerg Oster
Posts: 937
Joined: Fri Mar 10, 2006 4:29 pm
Location: Germany

Re: You make the call..

Post by Joerg Oster »

I think rule 6.9 must be applied here.

It's commonly agreed that 2 knights alone cannot force a mate.
Hence the result must be draw.
Jörg Oster
User avatar
Evert
Posts: 2929
Joined: Sat Jan 22, 2011 12:42 am
Location: NL

Re: You make the call..

Post by Evert »

Joerg Oster wrote:I think rule 6.9 must be applied here.

It's commonly agreed that 2 knights alone cannot force a mate.
Hence the result must be draw.
Even KNNK is not a draw under FIDE rules. Although it cannot be forced, two knights can deliver mate.