June 01, 2012
— Open Blogger Greetings to all the AoSHQ chess nerds, and you know who you are. I'm going to be away from the computer pretty much all day tomorrow, so I'm putting this week's chess thread up a day early.
More on the CN 7643 endgame problem
Last week, I put up an endgame problem that was driving me nuts, which I didn't know the answer to. And it stimulated a good discussion in the comments, which I found very gratifying. Thanks to you all, I think we now have a pretty good idea of the solution, and it's a win for White.
Here is the problem:
White to move
In these types of problems, I always start out by asking, what can Black do to f@*! White up? Well, Black only has one real threat, which is his advanced a-pawn. His strategic goal is to bring his King over and capture the White pawns. In order to do this, he needs to figure out how to leverage his main threat to tie White up in defense so the Black King has time to make a break for it over to the other side of the board.
For White's part, he needs to not get too far behind Black's march to the king-side, and also, he cannot afford to part with the Knight. If, for example, he trades Knight for pawn, he's dead, as Black has now got the drop on him over on the King-side.
The position starts out with Black pretty much in zugzwang, which White can exploit
1. h3 Kd2
Black really doesn't need to go to b1 to defend the pawn, as some commenters have suggested. White really can't take the pawn, at least not yet. If Kxa2, then Kxc2 and Black now goes over and scoops up the pawns.
2. Kb2 Kd3
This pretty much nullifies Black's queening threat. The King can stay on b2 for a time while White uses his Knight to duel with the enemy King.
3. Nb4+ Ke4 4. Nc6 Kf3 5. Nd4+ Kg3 6. Nf5+ Kxh3 7. Nxh6 Kg3
It's pretty much over at this point. White can now take the a-pawn and then join the fray on the other side of the board. If Black tries to manoeuver his King around to attack the Knight, it can go to f5. A typical continuation might be:
8. Kxa2 Kf4 9. Kb3 Ke5 10. Kb2 Kf6 11. Kc3 Kg6 12. Nf5 Kf6 13. Kd4 Ke6 14.
Ng7+ Kf6 15. Nh5+ Ke6 16. Ke4 Kf7 17. Kf5 etc.
Thanks to moron commenters Philip, DJ, rtw, TSgt Ciz, MFG, CAL and others for providing analysis.
Commenter MFG had an interesting idea, inspired by one of his correcspondence games:
1. Na1 Kb1 2. Kc3! Kxa1 3. Kc2 h5 4. gxh5 g4 5. h6 g3 6. h7 gxh2 h8B mate
Very clever, but I think Black can avoid it by not taking the Knight. Instead, his second move should be Kc1 and now it's unclear how White can make any progress in this new direction without having it morph back into the main line.
What a fun problem. Again, thanks to Edward Winter's excellent Chess History site for it.
Rook and pawn endgames are always complex and ripe for discussion. This particular one is from the 1st issue of Chess, a British magazine published in 1935. It's not the BCM, I believe.
Bogoljubov (White)
The magazine text reads: "Bogoljubov gave this up as a draw. Actually, he could have won. How?"
Game of the Week
This week's famous chess game is Alekhine v. Yates, 1922. White gets an open file, and then seizes some crucial dark squares, and then finishes it off with a surprising sacrifice.
You can play through it yourself here.
Thanks to those of you who have sent me tips for this thread. They may be sent to me at
OregonMuse
and then the at sign
followed by yahoo
and then dot
com
See you next week!
Posted by: Open Blogger at
03:10 PM
| Comments (63)
Post contains 683 words, total size 4 kb.
Posted by: RioBravo at June 01, 2012 04:01 PM (le4UT)
Posted by: Kate Upton at June 01, 2012 04:03 PM (O2ehV)
Posted by: The inexplicable Dr. Julius Strangepork at June 01, 2012 04:04 PM (XCAcw)
Posted by: Anson Mitchell at June 01, 2012 04:07 PM (IhUxK)
Kd5... Black ALWAYS has to defend against W's Pc8->Q checkmate.
Don't know how B can do it as long as W keeps its K off the dark diagonal (avoids B's P->Q check.) The rook can's check along the 6-row and going Ra5 is just a race
Kd5 Ra5+
Kc4 Ra4+
Kb3 ???
Any deviation from checking the white king results in white win. Unless I missed something major and should be embarassed. Which I feel I am since they didn't play it out...
Posted by: Tonic Dog at June 01, 2012 04:13 PM (X/+QT)
Posted by: someguy at June 01, 2012 04:18 PM (sEXZ/)
Posted by: Steevy at June 01, 2012 04:20 PM (Ts9tU)
Posted by: Navin R Johnson at June 01, 2012 04:23 PM (HpT9p)
Posted by: fluffy at June 01, 2012 04:25 PM (4pSIn)
Posted by: Merovign, Dark Lord of the Sith at June 01, 2012 04:26 PM (bxiXv)
Posted by: huerfano at June 01, 2012 04:28 PM (bAGA/)
Did I accidentally cross the International Date Line? Again?
Maybe. Is this song playing in your head? http://tinyurl.com/568je6
Posted by: fluffy at June 01, 2012 04:31 PM (4pSIn)
Posted by: Cicero at June 01, 2012 04:39 PM (QKKT0)
Posted by: Anson Mitchell at June 01, 2012 04:40 PM (IhUxK)
how did whites king get into check ???? the pawn hasnt moved and you cant "move into check" did I miss something or is this a bs scenario ?
Posted by: alec at June 01, 2012 04:41 PM (5RTXq)
how did whites king get into check ???? the pawn hasnt moved and you cant "move into check" did I miss something or is this a bs scenario ?
No, it's a position from an actual game. And in the game, White is currently in check. So the first move has to be a move that gets White out of check.
Posted by: OregonMuse at June 01, 2012 04:46 PM (xm1A1)
Posted by: Guy With A Lot Of C-4 at June 01, 2012 04:48 PM (PI8zr)
how did whites king get into check ???? the pawn hasnt moved and you cant "move into check" did I miss something or is this a bs scenario ?
In 'The Tricky Endgame'?
It is white to move. Both players have advanced a pawn to the 7th rank and are the verge of queening.
Posted by: fluffy at June 01, 2012 04:49 PM (4pSIn)
Posted by: One Night in Bangkok at June 01, 2012 04:49 PM (Y+DIS)
Posted by: alec at June 01, 2012 04:50 PM (5RTXq)
oh craaaaap ! im a dumbass ! I needed to turn the board around , sorry for waisting your time
These are the thoughts going through my head after getting thumped by someone rated 400 points above me ;--)
Posted by: fluffy at June 01, 2012 04:52 PM (4pSIn)
Posted by: airandee at June 01, 2012 04:55 PM (9GHCK)
Posted by: Debbie Whattaslag-Schlitz at June 01, 2012 04:57 PM (MMC8r)
Posted by: Todd W at June 01, 2012 05:01 PM (lrkg9)
Posted by: crappola online at June 01, 2012 05:14 PM (taJSi)
Posted by: mama winger at June 01, 2012 05:18 PM (P6QsQ)
Tonic Dog...
When you go Kc4, I'd go Ra8...
Then I'd likely be able to take both the pawn and exchange mine for the queen...
Posted by: Dilligas at June 01, 2012 05:18 PM (/Odq7)
There are chess-playing spambots here. I find this disturbing.
Do you see where he jsut put his knight?
Pfft! He can't play.
Posted by: fluffy at June 01, 2012 05:22 PM (4pSIn)
I think I'm the only one who got that.
"I'm huuurt, and I'm confuuused, and I don't know what to say. No comment!"
Posted by: Navin R Johnson at June 01, 2012 05:24 PM (HpT9p)
I see it more as:
Kd5 Ra5+
Kc6 Ra6+
Kb7 ... Rook must abandoned at this point... Pa1 exchange for queen
Pc8 - exchange for queen and mate...
Posted by: Dilligas at June 01, 2012 05:25 PM (/Odq7)
Try this for the draw:
White moves first, and balances protecting the White Pawn with going after the Black Pawn
Kd5 Ra8
Rh1 Rc8
Ra1 Kd7
RxP RxP
Posted by: Arbalest at June 01, 2012 05:31 PM (vLgEk)
If Rh8... then black must move to either D7, E7, or F7... a move to E7 or F7 are losers... D7 could have some play though...
black moving to D7 would drag out the game, but white could easily have king/rook versus black's king only...
Posted by: Dilligas at June 01, 2012 05:46 PM (/Odq7)
Ok, try this ... looks like a Black win:
Kd5 Ra5C
Kc4 Rc8
if White King moves, then Black Pawn to a1
so Rh8 Kd7
The White rook can chase the Black King back to B7 (via C6), but then White has no more check moves, and then Black Pawn to a1 ...
Posted by: Arbalest at June 01, 2012 05:46 PM (vLgEk)
Posted by: Arbalest at June 01, 2012 05:50 PM (vLgEk)
Regards to my #38... I erred... white exchanging for queen would not be mate... as black rook takes, then a mess of options...
instead of exchangint the pawn white moves Rh8+...
Black king to D7, E7, or F7... D7 appears to give best hope, but hopeless at this point...
Rxa8 ... black's move is irrelevant
Rxa1 (or Rxa2)... black move irrelevant
eventually exchange white pawn for queen and between queen and rook march to mate...
Posted by: Dilligas at June 01, 2012 05:54 PM (/Odq7)
White king to c4 is definitely a loser for white... why c6 would be the better option... forces black to maintain focus on the king...
if you move Ra7... white = Pc8 exchanged for queen and checkmate... black's threat on the white rook is meaningless...
Posted by: Dilligas at June 01, 2012 06:02 PM (/Odq7)
Posted by: Arbalest at June 01, 2012 06:14 PM (vLgEk)
Posted by: rtw at June 01, 2012 06:41 PM (pPmyV)
It's not at all clear he can do either for long. For example:
1 d5 a5+
2 c4 a4+
3 b3 isn't so good because of ... a3, so
3 d3 a3+
4 c2
and now what is black to do? There are only two checks available, neither particularly appealing.
4 ... c3+
5 b2
and I don't see anything happy in black's future
or
4 ... a1N+
5 b2
and again, though black can fight on with b3+, white certainly has a won game as far as I can see.
Am I missing something?
Posted by: pjf at June 01, 2012 07:46 PM (RM1zZ)
Posted by: rtw at June 01, 2012 07:54 PM (pPmyV)
Posted by: rtw at June 01, 2012 08:05 PM (pPmyV)
I think ... Rc6 takes away white's advantage. Looks drawish to me then.
White really has to worry about black's promotion now, so perhaps we get something like:
2. h8+ d7
3. Ra8 is pretty much forced, I think. Playing around with checks like 3. Rh7+ looks really dangerous for white.
Then after 3. Ra8, there really isn't much to do but exchange pawns eventually.
Posted by: pjf at June 01, 2012 08:23 PM (RM1zZ)
Posted by: waelse1 at June 01, 2012 10:57 PM (VaU8E)
1. Kd5 Ra5+
2. Kc4 Ra4+
3. Kd3 Ra3+
4. Kc2
and I don't see how black can avoid losing. If Rc3+ then white plays Kb2 stopping the pawn from queening. I'm probably missing something though.
Someone suggested moving the king to b7 but then black plays Ra7+ and if white takes the rook he plays a1-Q+ and black should win. The rook is invulnerable on the a-column.
Posted by: waelse1 at June 01, 2012 11:19 PM (VaU8E)
1 Kd5 Ra5+
2 Kc4 Ra4+
3 Kb3 Ra3+
4 Kc2 Rc3+
5 Kb2 a1Q+
6 Kxa1 Rc2
7 Kb1 Rc3
8 Kb2 Rc6
9 Kb3 Rc5
10 Kb4 Rc1
11 Kb5 Rc2
12 Kb6 Rc3
13 Kb7 Rb3+
14 Kc8 followed by Rh7-h4-a4-a7-b7, Kb8, and c8Q. If Black at some late stage returns his R to the c-file, White will R-bfile-b6, Kb7 etc.
The King gets his exercise in this one!
Posted by: Adjoran at June 01, 2012 11:54 PM (VfmLu)
Someone suggested moving the king to b7 but then black plays Ra7+ and if white takes the rook he plays a1-Q+ and black should win. The rook is invulnerable on the a-column.
I disagree... if black checks with the rook on a7... the white king takes it. If black then moves forward to a1 for the queen - yes, it puts white back in check, but white just moves back to b7 out of check...
Black is then forced to constantly keep white is check with his queen and figure out a way to separate the king from the pawn - else as soon as white is not in check, he moves the pawn forward for check mate.
As well, even if the queen can get to row 8 in a position to take the pawn, white moves his rook to row 8 to put black into check. Pending the location of the white king, it could be check mate - or the queen is then lost and just a matter of time before black loses.
At best, lacking a serious mistake from white, black can only hope for a draw.
Also, as noted above, white king to c4 appears to be a potential mistake... it separates the pawn and king and at best - it's simply a pawn exchange, but black comes out slightly ahead with a king/queen combo versus white's king/rook.
Posted by: Dilligas at June 02, 2012 05:03 AM (/Odq7)
Posted by: rickl at June 02, 2012 05:43 AM (sdi6R)
Yes, of course you're right.
There is nothing at all wrong with 3. Kb3. For some reason I was only thinking of 4. Kb2. That's why I'm not a chess player.
Posted by: pjf at June 02, 2012 05:48 AM (RM1zZ)
In looking at it a bit harder... c4 is not a loss for white, but makes things much more difficult and drags out the game... it appears the best black can hope for is a draw and should have jumped on the opportunity when presented.
Still believe the shorter version is:
1. Kd5 Ra5+
2. Kc6 Ra6+
3. Kb7 ... rook must move to a8 else game is over... Ra8
4. Rh8+ ... king must move to d7, e7, or f7... even if moving to d7, black cannot take the pawn due to white king at b7
5. Rxa8 ... black's move is essentially pointless - king moves or exchange the pawn
6. Rxa1 or Rxa2 pending the exchange... black is now left with only a king and is helpless to keep white from exchanging for the queen and can only drag out the game by fleeing
Posted by: Dilligas at June 02, 2012 07:18 AM (/Odq7)
take it back... if 3. Kb7 Ra7+... black can still get a draw...
Posted by: Dilligas at June 02, 2012 07:38 AM (/Odq7)
Posted by: Philip at June 02, 2012 07:38 PM (ze3Ei)
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Posted by: SantaRosaStan. uber alles at June 01, 2012 03:56 PM (Dll6b)