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| Sep-06-08 | | johnlspouge: I thought 65.Qe8+ forced mate, which of course it does not. Mysteriously, my memory leapt ahead of my logic. I have seen the position before, but given that the game has not been a game of the day, I am mystified where I saw the position or the theme. |
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| Sep-06-08 | | hms123: Here's a knight's pawn trap to be avoided.
click for larger view
White to move: <1. b5 Ka8 2. b6?? draw>
click for larger view |
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| Sep-06-08 | | patzer2: For today's Saturday puzzle solution, White wins a difficult Queen and pawn ending with a pair of mating threats. First, White plays 64. Qc6!! to threaten 65. Qb7# and force 64...Qb4, since the only plausible alternative is 64...Qd3+ when 65. Qb5+ results in the won King and pawn endgame described by <Jimfromprovidence>. Secondly, White follows with 65. Qd7! when Black can stop the threat of 66. Qd8# only at the expense of yielding to the alternative threat of 66. Qb7# (i.e. 65. Qd7! Qf8 66. Qb7#). |
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| Sep-06-08 | | MarvinTsai: His family name is Ye. |
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Sep-06-08
 | | sleepyirv: It's not that I'm getting better, right? These puzzles are just easy, right? Though it would build a lot of self-confidence if I get every puzzle this week. C'mon Chessgames.com! |
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| Sep-06-08 | | whiteshark: ♔♕ are in close contact with ♔. |
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| Sep-06-08 | | kevin86: Six pieces! In a Saturday puzzle! WOW!
White threatens mate in two places-there is NO defense. |
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Sep-06-08
 | | al wazir: <Manic: You missed that after 64...Qb4 65.Qb5+ black doesn't have to take as the queen is protected. Simply 65...Kc8 holds the draw (I think), as after 66.Qxb4+ axb4 67.Kb5 Kb7 and black has opposition.> The white ♔ is in front of the ♙. White can always promote when this is true (unless it's the a- or h-♙). |
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| Sep-06-08 | | unsound: <The white king is in front of the pawn. White can always promote when this is true (unless it's the a- or h-pawn).> Misleading nonsense. See <JimfromProvidence> above. But <MostlyAverageJoe> shows how white can always get the opposition in that particular position. |
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| Sep-06-08 | | TheaN: 5/6
This, is... way too stupid. I was looking at the position 64.Qc6 Qb4 for ten to fifteen minutes; knowing that 64.Qxa5 would be a long and dreadful ending after 64....Qd1 (seeing now that Qd6† DOES actually work for Black also: 65.Qb6† Kc8!? (Ka8!) 66.b4!), but I couldn't simply find 65.Qd7. 65.Qb5† wins, but that's probably even worse to play out than 64.Qxa5 Qd1, so not a right solution. No point for me, and that sucks. |
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Sep-06-08
 | | Jimfromprovidence: The Nalimov endgame table bases, as earlier described by <MAJ>, are an excellent learning tool. This match would be a good example to use to illustrate its benefits. After 52…Qxa2, there are six pieces left on the board. 
click for larger viewWhen you plug the position into the tablebase applet it will tell you that the position is a draw. Even better, the tablebase will tell you the correct successive moves to maintain the draw. Compare those moves with the moves in the actual game and you will find out where black went wrong. Here is the position after 63 Qc5.
click for larger viewThe table base applet tells you that black must play 63…Qd7 to draw and that either Kb8 or Kd8 lose. Black chose 63…Kb8 and thus gave us today’s puzzle. |
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| Sep-06-08 | | stukkenjager: Since when is a win in 24 moves easy?? |
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| Sep-06-08 | | Once: <stukkenjager> ... when your chess engine is doing the hard work! |
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| Sep-06-08 | | Once: <The white king is in front of the pawn. White can always promote when this is true (unless it's the a- or h-pawn).> Well, yes and no. This statement is true when the pawn is well advanced (ie on the sixth rank) ... 
click for larger viewWhite wins, whether it is his move or not. With black to move: 1. ... Kd8 Kf7 and the pawn will run through to queen. White to move: 1. Kd6 Kd8 2. e6 Ke8 3. e7 Kf7 4. Kd7
But rewind the pieces one or more ranks and it's a subtly different story. 
click for larger viewNow if it is white to move we have a draw. Black keeps the opposition and the only thing that white can do is push the pawn ahead of his king. 1. Kd5 Kd7 2. e5 Ke7 3. e6 Ke8 4. Kd6 Kd8 5. e7+ Ke8 6. Ke6 1/2-1/2 But if it black to play, white wins. Eg. 1... Kd7 2. Kf6 Ke8 3. e5 Kf8 4. Ke6 Ke8 reaching our first position (which we know to be a win for white). Why should it matter which rank the pawn is on? With the pawn on the fifth rank or earlier, black has enough room to get in front of the white pawn. But with the pawn on the sixth, black finds himself needing a ninth rank. Okay, too many words. Let's do it with a diagram.
click for larger viewWith black to play, he draws with 1. ... Ke8. The white king and pawn cannot get him off the queening square. But shove everything one rank forward and we get this position. 
click for larger viewNow black would dearly love to play 1. ... Ke9 following the pattern from the last diagram. But that's only allowed on Star Trek. Here on earth, he has to play 1. ... Kf7 when 2. Kd7 and e8=Q follows. |
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| Sep-06-08 | | MostlyAverageJoe: <stukkenjager: Since when is a win in 24 moves easy??> It depends. The optimal (in the sense of delaying the mate by most moves) defense line for the black is actually easy to win: 64.Qc6 Qe2/d3 65.Qb5+ Qxb5+ 66.Kxb5
click for larger view
and it is clear that white K will maintain the necessary separation from its pawn to be able to win. Yes, there are 20 more moves and countless winning lines, but there is no need to think a lot. The post by <Once> explains the principles. It is much trickier to win after 64.Qc6 Qb4?! if one does not find the best response of 65.Qd7 and plays 65.Qb5+ instead. After: 64.Qc6 Qb4 65.Qb5+ Kc8
click for larger viewWhite must now find 66.Qf5+ to win. However, consider that taking the black Q would be a mistake as the black K will close the gap and draw: 66.Qxb4? axb4 67.Ka5/b5 Kb7 68.Kxb4 Kb6
click for larger viewTherefore, 66. Qf5+ should be considered and now:
click for larger view
if Kc8 the Qd7 calls to be played (otherwise we get a repetition), and if Kc7/Kd8, then Qxa5+ forces the exchange and again it is easy to see that the white can maintain the separation from its pawn and win. The difficult part of today's puzzle is really finding all moves that will lead to a draw and discarding them. What's left is the winning line :-) |
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| Sep-06-08 | | TheaN: <al wazir: The white K is in front of the P. White can always promote when this is true (unless it's the a- or h-P).>
click for larger viewSorry, I don't see a win or promotion for White...
Meh, lame :). You have been told what the exception is to the rule you've stated, which is: 
click for larger view...after 1....Ke6. Principally, White can try three things: 1) break Black's opposition with a pawn move: 2.Kd4 Kd6 3.e4 Ke6 and White loses his position in front of his pawn with a draw: 4.e5 Ke7 5.Kd5 Kd7 6.e6† Ke8 7.Kd6 Kd8 8.e7† Ke8 9.Ke6 1/2-1/2., but the last five moves should be a known tactic. 2) roam around the fourth rank hoping Black gives away opposition: 2.Kd4 Kd6 3.Ke4 Ke6 4.Kf4 Kf6 5.Ke4 Ke6 1/2-1/2. 3) or lose the position is front of the pawn with Kf3 or Kd3 and draw: 2.Kf3 Ke5, and see option 1 for the continuation. Ingame, the two trading possibilities don't work for White. If <65.Qc6 Qb4, 66.Qb5†? Kc8!> and White should watch out to play Qf5† and keep the Qd7 threat alive, as <67.Qxb4? axb4 68.Kb5 Kb7> and the Black is where he is needed: 
click for larger view<69.Kc5 (Kxb4 Kb6) Kc7 70.Kc4 Kc6 71.Kxb5 Kb7 1/2-1/2> Ironically, Black can also utilize the drawing option of the K+rookP vs K in: <65.Qc6 Qb4 66.Qb6†??> deserves two question marks as it's just careless: <66....Qxb6! 67.Kxb6 a4!:> 
click for larger view<68.bxa4 (b4?? a3  !) Ka8 1/2-1/2> |
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| Sep-06-08 | | TheaN: With the trading possibility after 66.Qb5† Kc8 67.Qxb4, I obviously mean <71....Kb6> and not Kb7: <65.Qc6 Qb4, 66.Qb5†? Kc8! 67.Qxb4? axb4 68.Kb5 Kb7 69.Kc5 (Kxb4 Kb6) Kc7 70.Kc4 Kc6 71.Kxb5 Kb6 1/2-1/2> That I all DO have, missing 66.Qd7. |
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| Sep-06-08 | | TheaN: Ironically (sorry for triple post), in my final example:
click for larger view<68.bxa4 Kc8?!> draws too, although it's just stupid. Fritz immediately gives 69.a5 with a simple draw, but of course White should try <69.Ka7>: 
click for larger view...which can be tricky. However, this is a very famous stalemating trick from the losing side: <69....Kc8! 70.a5 Kc7 71.a6 Kc8 72.Ka8 Kc7 73.Ka7 Kc8 74.Ka8 Kc7 75.a7 Kc8 stalemate 1/2-1/2>. If white tries to play Kb6, where the position of the a-pawn does not matter, Black gains a8 back with Kb8, with a draw. |
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| Sep-06-08 | | TheaN: Switch all the Kc7 and Kc8 and get the correct sequence; man it's too late here to be posting true analysis. |
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| Sep-06-08 | | DarthStapler: Doesn't Qb5+ also work? (after Qb4) |
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Sep-07-08
| | al wazir: Thanks to all who have attempted to supply remedial endgame instruction. My games seldom reach the endgame, so I don't really need to know this stuff. (It's sort of like taking flying lessons and not bothering to learn how to land.) |
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| Sep-07-08 | | TheTamale: Actually, Al Wazir, many strong players recommend learning end game theory even over the openings. It's good to know what you're shooting for. Although I understand your point--it's frustrating if you never get there anyway... my games are the same way! But it'll be even worse once you do start getting there & then blow won games because you didn't know how to proceed. |
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| Sep-07-08 | | TheaN: <(It's sort of like taking flying lessons and not bothering to learn how to land.)> With this, I think you defy your own example: isn't it the fear of crashing halfway through, that one does not want to know how to land so he doesn´t actually have to try get there? How cryptic it might be, the same applies to chess: if you know how and what in chess endgames is won or drawn, you could try to steer it that way and still salvage half or a whole point, and thereby avoiding a quick loss in the endgame with the idea "that I'm going to lose the endgame anyway". It's an important barrier to breach, and even I haven't breached that yet as in practice I screw up at endgames. |
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| Jan-02-09 | | WhiteRook48: what an ending! White threatens two checkmates! Then he queens the b-pawn. |
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| Jun-18-18 | | Omnipotent00001: 48...a4 is a draw. |
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