< Earlier Kibitzing · PAGE 3 OF 3 ·
|Dec-26-10|| ||Domdaniel: I toyed with the notion of 36...Bf6+ as a desperate attempt to lure the big guns - and the soon-to-be-big gun on e8 - away from the mating square g6. No hope.|
Then I realized that 36...Nxf4 also covers the key square, and that White can't really reply 37.e8Q because of ...Ng2+ 38.Kg4 Qd1+ and at least one Queen drops. But White can take a perpetual instead. I didn't see that much of the complicated stuff, though.
The line in the game was ... interesting. Where could *this* possibly lead, I thought -- then realized that the sad truth was "precisely nowhere".
|Dec-26-10|| ||Patriot: White threatens 37.Qxg6# and 37.e8=Q. Therefore my candidates were ...g5+, ...Ne5, ...Nxf4, and ...Qe4.|
I tossed out 36...g5+ because of 37.fxg5+ immediately. Then after spending some time with 36...Ne5, the simple 37.e8=Q troubled me. 36...Nxf4 37.Qxf4+ seemed odd, but only because I didn't even notice that black is up a piece for a pawn!
So...I opted for 36...Qe4, seeing that 37.e8=Q g5+ 38.Kg4 Nf2#. Also, 37.Qxg6+ Qxg6 38.Bxg6 Bf6+ 39.Kg4 Bxe7 40.Bxd3 d4 looks better for white.
I made a similar mistake as yesterday, plus another one. I failed to see all the critical candidates (i.e. 36...Qe4 37.Bxg6) and I erroneously discarded 36...Nxf4 due to 37.Qxf4+ since I didn't count material.
Consistently counting material is good practice even if it means taking a little longer on the "very easy" and "easy" puzzles. This has a direct impact on what lines you look at and which lines you discard.
Plus it's always a good idea to look at the most critical variations first because you can end up wasting a lot of time on variations that won't happen. This way if a candidate can be refuted it's more likely it will be done at the beginning of your analysis and you can move on to a better candidate. There were several candidates today that were critical after 36...Qe4 -- 37.e8=Q, 37.Qxg6+, and 37.Bxg6 (the one I missed). Missing just one critical candidate can cause you to make the wrong decision so it's important to see all of them, starting with the most critical first.
This is why Saturday and Sunday puzzles are good practice. Usually everything is in a delicate balance which really is a good test of our analytical skills. Most of the week the win is clear and not much analysis is even required.
Perhaps other kibitzer's made similar mistakes?
|Dec-26-10|| ||WhiteRook48: i tried ne5 with some swindle tries|
|Dec-26-10|| ||Domdaniel: <Patriot> Yes, checking material balance is a good idea, usually -- but it only really matters when there's a safe route out to calmer positions where you're a piece (or whatever) ahead. In these chaotic positions it hardly matters at all -- except, of course, as a factor in evaluating those quieter positions at the end of certain lines.|
That doesn't sound as if it makes much sense...
|Dec-26-10|| ||patzer2: For today's Sunday puzzle solution, which I only got after a superficial guess, Black finds an amazing drawing resource with 36...Nxf4!!|
Here's some analysis with Fritz 10 to help in understanding the tactics involved:
36... Nxf4!! 37. Qxf4+ Kh7 38. Bxg6+! this apparently forces a perpetual after
[less strong is 38. Qf7?! Qe4+ 39. Bg4 dxc4! 40. e8=Q ?? (relatively better here is 40. Qe6 Qxe6 41. Bxe6 Bf6+ 42. Kg4 Bxe7 43. Bxc4 Bf6 44. b3 a6 with only difficult drawing chances for White) 40... Qxe8 41. Qxe8?? Bf6#]
38... Kxg6 when play might continue 39. Qg5+ Kf7 40. Qxd5+ Kxe7 41. Qxc5+ Ke8 42. Qh5+ Kf8 43. Qf5+ Ke8 44. Qg6+ Kf8 45. Qf5+ Ke8 46. Qg6+ Kf8 47. Qf5+ = with an apparent draw by perpetual check.
|Dec-26-10|| ||Patriot: <Domdaniel> What you said does make sense. When dynamics are involved, material doesn't matter as much. But I think that being aware of material imbalances makes it clearer when material can simply be given back. For example, the likelihood of sac'ing a queen for a rook is higher when they are already up a piece and a pawn. In this problem, I decided 36...Nxf4 was bad because I really thought material was even.|
This knowledge helps in move-by-move decisions and helps eliminate biases of giving up material where it is only giving it back or isn't giving up an entire piece when you're already up 2 or 3 pawns. Also I think it helps in analyzing more efficiently because if you know what you're starting with and can keep track of what is being exchanged along the way, then you won't have to count up material at the end of each line when the smoke is clear. It can also provide you with a good feel of whether you might be wasting time. For example in cases where you are going way out on a limb after giving up significant material it could be a sign you need to back up and look for a simpler approach if there is one.
In chaotic positions, I think it is more important to know material imbalances because there is a lot of decision-making. On Monday puzzles, it's usually a waste of time because there is a forced mate or an obvious way of gaining material without much resistance.
|Dec-26-10|| ||dstroyer: i went for 36. ... Ne5 and i calculated some variations and the only one i could see when white is abel to hold a draw is 37.e8 Qe4 38.Bxg6 Nf3+ 39.Kg4 Nh2+ 40.Kh4 Nf3+ and so on.|
|Dec-26-10|| ||newton296: got Nxf4 almost on the spot. what else is there to prevent mate at g6. but then if white play e8Q its tough to find all of black's mate threats that hold the line up. |
I just figured Qxf4+ kh7 Bxg6 and black could hold. so can't really say I get full credit.
|Dec-26-10|| ||M.Hassan: "Insane"
Black to play 36.....?
Black is ahead by a Knight for a pawn.
White is one move away from promotion of e pawn.
The move that appeals to me is
In response, White can promote the pawn or take the Knight. Let us consider each case:
Black manages to get both Queens, falls ahead in material and likely wins. I don't think the game has followed this line.
The other likely line is:
And I don't see an immediate win in this line and I think forces are equal.
Acual game???: Entirely different
|Dec-26-10|| ||gofer: Well I looked at 36 ... Ne5 and it seemed pretty good, but then I looked at what happens after 37 e8=Q and
I realised that black is in trouble. So I had to discard it! So I then looked at the only possibility;
36 ... Nxf4 which seems to be rather good!
<36 ... Nxf4>
37 e8=Q Ng2+ 38 Kg4 Qd1+ 39 Qf3 Qd4+ 40 Qf4+ Nxf4 winning
<37 Qxf4+ Kh7>
Now we get to the interesting bit! What can white do now? Qf7 or Bxg6+
38 Qf7 Qe4+ 39 Qf4 Qxe7+ (Bg4 Kh6 winning) winning
<38 Bxg6+ Kxg6>
<39 Qg5+ Kf7>
<40 Qxd5+ Kxe7>
<41 Qxc5+ Kf7> (Qxb7+ Kf6 Qxa7 Kg6 winning)
<42 Qxa7 Bf6+ winning>
Time to check...
|Dec-26-10|| ||stygian: Well, right or wrong, my choice was 36...Nxf4. I wish that I could say that I looked at all the continuations. But to me, it looked like it was black's only chance to eke out at least a draw. Kudos to those who followed the lines further. Good puzzle, IMHO.|
|Dec-26-10|| ||DarthStapler: I made the same mistake as Dzechiel|
|Dec-26-10|| ||wals: Rybka 4 x 64
BLACK: depth : 21 : 4 min :
(+14.50):36...Qe4. Best, Nxf4, =0.00.
1. = (0.00): 36...Nxf4 37.Qxf4+ Kh7 38.Bxg6+ Kxg6 39.Qg5+ Kf7 40.Qxd5+
and a draw by three fold repetition.
BLACK: depth : 14 : 3 min :
Black avoided checkmate by resigning
move 41... .
At move 26.e6, Black had an advantage of -0.80.
26...Nd3+, =0.00, the advantage was lost.
The scores remained equal until the disatrous move 36..Qe4.
|Dec-26-10|| ||ravadi: How would Black save the game after 36....Nxf4 37.Qxf4+ Kh7 38.Bxg6+ Kxg6 39. Qg5+ Kf7 40.Qh5+ I don't see any defense for Black in this position. Any input would help me in understanding this better.|
|Dec-26-10|| ||Beandip: <ravadi> After 40.Qh5+, black can play Kxe7. Black is then up a bishop and should be winning. White can't force a draw by perpetual because any check will lose the queen.|
|Dec-26-10|| ||ravadi: <Beandip> Thank you. I completely overlooked the power of King!!|
|Dec-26-10|| ||BOSTER: After 33...h4 white quickly played 34.Kxh4,who would like to play 34.Kh2. My guess that this bold move wins the game for white.
34.Kh2 if Nf2 35.g3
if Qe1 35.e8=Q Qg3+ 36.Kg1 Qf2 + 37 .Kh1 Qf1+ 38.Kh2 Nf2 39.g3 Qxh3 40.Kg1 Qxg3 41.Bg2.
|Dec-26-10|| ||Eyal: <BOSTER: who would like to play 34.Kh2. My guess that this bold move wins the game for white. 34.Kh2 if Nf2 35.g3>|
Actually White is losing here, but it's far from obvious: 34.Kh2(??) Nf2 35.g3 hxg3+ 36.Kxg3 (36.Kg2 Qh1+ comes to the same thing) 36...Qg1+ 37.Kh4 (37.Bg2 Ne4+ with mate on g3 in two more moves) 37...Qe1!
click for larger view
and the only way to prevent ...Ne4+ followed by mate on g3 is 38.Qxg6+ Kxg6 39.e8Q+ Qxe8 40.Bh5+ & 41.Bxe8, where White remains "only" a piece down - but still in a hopeless position, of course.
A couple of moves earlier, Black could gave forced a draw with a similar idea - 32...Qe1+ (instead of h5) 33.Kh2 Nf2 34.e7 Qh1+ 35.Kg3 Qe1 - but here ...Ne4+ followed by ...Qg3+ lead only to perpetual if the white king goes to h2.
|Dec-26-10|| ||Patriot: <BOSTER> You guessed wrong, no offense. I analyzed myself for a short time and figured 34...Nf2 35.g4 hxg3+ 36.Kxg3 Qg1+ (36.Kg2 Qh1+ 37.Kxg3 Qg1+ transposes) and white must play 38.Kh4 Qe1 setting up a discovered check (according to Fritz). I only saw that 38.Bg2 Ne4+ 39.Kf3 Qf2+ (39.Kh4 Qf2+ 40.Kg4 Qg3# OR 39.Kg4 Qxg2+ 40.Kh4 Qg3#) 40.Kg4 Qg3#.|
The bottom line is that 34.Kh2 loses. It's definitely complicated stuff.
|Dec-26-10|| ||sevenseaman: <eval> Nice to see correct analysis follow up <BOSTER>'s. I smelt a rat in <BOSTER>'s and was working on to unravel when yours came in. White got away with a steal.|
|Dec-27-10|| ||dstroyer: How do white win after 36. ... Ne5 37.e1(Q) Qe4 ?|
|Dec-27-10|| ||Phony Benoni: <dstroyer: How does white win after 36. ... Ne5 37.e8(Q) Qe4?> |
click for larger view
Very carefully, but with an extra queen he need only stop Black's threats (...Bf6+, ...g5+, ...Nf3+). 39.Qfe7 is probably a good way to start, followed by 40.Qg5+ and Black's threats are beginning to dissolve.
There are still a number of tricks, but White should be able to consolidate and win on material.
|Dec-27-10|| ||BOSTER: <Eyal> <about 34.Kh2>
You are right. Thanks.|
|Dec-31-10|| ||David2009: (Last Sunday's Insane problem) G Sagalchik vs A Kovalev, 1987 Black 36...? |
click for larger view
The mate threat on g6 seems to leave Black little choice: 36...Ne5 37 e8=Q Nxf7 38 Qxe1 (38 Qxf7!? is a dangerous try but why not pick up the Q?) Bf6+
39 Kg4 gxh5+ 40 Kf3 dxc4 and Black has counter-chances. The alternative 36...Qe4 fails to 37 e8=Q Qxe8 38 Qxe8 Bf6+ 39 Kg4 etc. Time to
Viewing the game continuation I am none the wiser, but at least I am better informed.
Wisdom comes from reading the kibitzes, in particular <plumbst> who finds the dazzling 36...Nxf4!! which I had rejected out of hand because 37 Qxf4 is with check. His full analysis is at G Sagalchik vs A Kovalev, 1987. <RandomVisitor> finds the same line a post or so later but let's give credit where credit is due.
After 36...Qe4?! (as played) my proposal 37 e8=Q?? loses a won game: 37...g5+! mates in two.
Rewind to White's 36th move (i.e. B at f3 in the diagram: White pleyed Bh5). Time to check against Crafty End Game Trainer with White to play 36 Bh5 (and not 36 e8=Q? Qxe8! etc):
The EGT finds Black wins against many White tries. Finding the perpetual check for White OTB against the EGT is tricky: stop reading now if you want to find it for yourselves.
Against the EGT you are white, drag and drop the move you want to make
Checking along the v rank seems simplest, <Once>'s recipe also works with very accurate White follow-up]
|Dec-31-10|| ||David2009: Congratulations <plumbst> first to solve last Sunday's truly insane puzzle. <perhaps: According to me, BLACK WINS with 36...g5+; 37.Kg4> 37. fxg5+ wins.
click for larger view
G Sagalchik vs A Kovalev, 1987 36...?
<coolthing76: Still can't find the point of the puzzle.> Black can find a miraculous draw starting with 36...Nxf4!! turning the tables.
The insanity is that White can recaptures with check - and then struggles to avoid defeat. See my previous post.
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