< Earlier Kibitzing · PAGE 3 OF 3 ·
|Jan-07-09|| ||YouRang: It might have been a little harder if our queen was not threatened. The fact that it was threatened sort of dictated the move order, which after all, was the key part of this puzzle.|
The ingredients were all there: A queen and rook (potentially 2 rooks) were targeting black's vulnerable h7 pawn, and our knight has a delicious square at f6. It's just a matter of putting it all together in the right order.
Having our queen in take suggests the immedate 24.Qxh7+ forcing 24...Nxg7. Now comes 25.Nf6 threatening the Arabian mate, and with Ra1 ready to join at h1, and with the royal knight fork if the king heads for f8, black has no escape that doesn't at least drop material.
|Jan-07-09|| ||DarthStapler: Got it|
|Jan-07-09|| ||Kasputin: Unlike yesterday, it would be hard to miss the possibility of a combination here. The question is: how to construct the combination if indeed there is a sound one.|
Like everyone else (I am guessing), the first thing that jumped out at me is a queen sacrifice with 24. Qxh7+ but then, however white follows up, it looks like the black king will escape a mating net via g7, f8, etc... I then thought briefly about 24. Nf6 and this would be fine if black doesn't take the queen with 24 ...gxh5, but of course black would take the queen in that instance. It was only through these ruminations that I thought, "well what happens if the king does escape the mating net - would there be another way to go after the king..." - at that point of course I saw that a king on f8 could be checked by the white knight moving to d7 and this would fork the black king and queen. Therefore:
24. Qxh7+ Nxh7
Now white threatens mate next move with Rxh7. There is only one move that can prevent this:
26. Rxh7+ Kf8
And next move of course, white will regain the queen. (Incidentally the black rook on c8 is attacked by the white knight and will have to move). The net result (at that point) is that white will have won a knight and a pawn. But the analysis shouldn't stop here. Since the white knight looks vulnerable on b6, can black trap it somehow?
Well it doesn't take long to conclude that even if the white knight disappeared from the board (i.e., nothing else changed in the position except that the knight disappears) that it might be worth it to play this line in any case. Afterall white gains a pawn and plants a rook on the 7th rank. Of course it won't be all rosy since that 7th rank rook isn't as valuable here as it might be in other situation (e.g., trying to double the rooks on the h-file and then trying to penetrate into the white position isn't all that promising, especially since black, with advanced pawns on the queen side of the board, has some potential counterplay).
But white's knight isn't really trapped. No matter what black's 27th move (which has to be either ...Ke8 or ...Ke7) and no matter what black does next to get his attacked rook out of trouble (e.g., by moving to attack the knight or moving it elsewhere like d8), white does have an escape square for the knight at a4. For instance:
27. Nd7+ Ke8 (or ...Ke7)
28. Nxb6 Rc6 (or Rb8)
29. Na4 and then what?
Even if black had played 28 ...Rc6 then 29 ...Bb5 is answered by 30. b3 and the knight is safe.
Of course if black doesn't play 28 ...Rc8 or 28 ...Rc6 then white might choose, temporarily at least, to leave the knight on b6.
But that isn't the end of the story either. Once 28. Nxb6 is played (i.e., to remove the black queen), I think that white has another possible line of play that would need to be looked at: It might be a good idea, instead of playing Na4, to play instead Nxd5.
The reason for a possible Nxd5 (assuming black hasn't prevented it with 28 ...Rd8) is that white would sacrifice his knight for two pawns (and have an overall material advantage of 3 pawns). But it would also open up the position to white's bishop (a bishop now aimed at a weakened f7 pawn) and go a long way to killing anything productive for black on the queenside.
Conclusion: white comes out with a won position - the only question, which doesn't need much attention until black's queen comes off the board, is what white should do with the knight? - should it be saved by moving to a4 or is there something even more productive, namely the elimination of black's central pawns with a well-timed Nxd5?
But that question can wait until white gets to that stage.
Time to check.
|Jan-07-09|| ||BlackWaive: I looked at this puzzle for two minutes, in Blitz mode.|
I immediately considered 24. ♕xh7+ ♘xh7 25. ♘f6 ♔g7 26. ♖xh7+, seeing the Arabian Mate theme. However, I discarded this line because the King escapes with 26...♔f8. I guess my Blitz strength is only 6-ply.
|Jan-07-09|| ||Kasputin: I didn't think about the move 25 ...Rg7, which I really should have for a complete analysis. It is not hard to see moving that other white rook over to h1 but that point is that I should have considered this.|
<TheaN> wrote <29.Na4 seems definitely the best move, as Nxd5 will be impossible in a long run.>
Isn't it fair to say that it is only impossible if black prevents it? If white has the opportunity to sac the knight for the 2 centre pawns, then maybe that is what white should do. Well I guess it hardly matters as Na4 can be played in any case.
|Jan-07-09|| ||notyetagm: 22 ♖h1-h2
click for larger view
What a beautiful KIA position White (Stukopin) has: a roaring 6(!)-piece attack down the open h-file.
|Jan-07-09|| ||notyetagm: <Kasputin: I didn't think about the move 25 ...Rg7, which I really should have for a complete analysis. It is not hard to see moving that other white rook over to h1 but that point is that I should have considered this.>|
You just have to consider such a defense to the h7-square mating threat as 25 ... ♖g8-g7 in advance.
If it had worked, you would have just lost ♕ for ♙.
|Jan-07-09|| ||Patriot: Material is even. White has a great deal of pressure down the h-file with the a1-rook ready to swing over. But right now white's queen is hanging so Qxh7+ or Qh6 to maintain the grip on the h-file come to mind.|
A) 25.Rxh7+ Kxh7
AA) 26.Nf6+ Kg7 27.Rh1 Rh8
AB) 26.Rh1+ Kg7 27.Nf6 Rh8
BA) 25...Rg7 26.Rah1 and black is getting mated with 27.Rxh7+ Rxh7 28.Rxh7#
BB) 25...Kg7 26.Rxh7+ Kf8 27.Nd7+ and 28.Nxb6 wins a knight and a pawn
Now let's try Qh6:
Now there are two serious threats: 25.Rah1 and 25.Nf6
24...f5 25.Nf6 Rg7 and black seems to be holding on.
At this point I would decide that 24.Qxh7+ is the best move.
|Jan-07-09|| ||Once: The problem with looking at these positions after work is that it has all been so well said by others. So I am left scratching round for something new to say.|
Oh, well, here goes ... er ...
24. Qh6 also seems strong (although obviously less decisive)
Isn't it great that a player called Stukopin should win by a pin on the h file? No?
For what it's worth, I spent an inordinately long time trying to get 25. Rxh7+ to work, before stumbling on 25. Rah1, finding 25...Kg7 and then arriving at 25. Nf6. Those who spotted the full line in an instant humble me. But as I always say about golf, amateur players get better value for money than Tiger Woods because we get to play more shots per round ...
|Jan-07-09|| ||ZUGZWANG67: I struggled a bit on this one and it seems that my solution is not exactly the one showed in the actual game. Or is it ?|
I first noticed the Q sac at h7 but after 24.Qxh7+ Nxh7 25.Rxh7 Kxh7 26.Nf6+ Kh8 27. Rh1+ Kg7 28.Rh7+, Black has 28. ...Kf8. The departure of the BN from f8 gives the BK an escape hole.
I then gave up investigating the immediate Q sac at h7 and instead considered a slightly different way of ending things, and it seems as good as the actual solution. Here it is: 24. Nf6 Rg7 (forced) 25. Rah1 (see diagram)
click for larger view
. ... adlib (25. ...h6 26.Qxh6+ Nh7 27.Qxh7+ Rxh7 28.Rxh7+ mate) 26. Qxh7+ Nxh7 27.Rxh7+ Rxh7 28.Rxh7+ is mate.
In fact it seems that in the solution given in the actual game, Black always has . ...Rg7 and White always has to answer with Rah1, which amounts to the same thing. Compare with 24.Qxh7+ Nxh7 25.Nf6 (as in the game) and you still have that 25. ...Rg7 26.Rah1 adlib 27.Rxh7+ Rxh7 and 28.Rxh7+ is still mate in 28 moves. In fact, there are so many pawns on the board that in both lines, Black, at some point, runs out of moves when comes the time to provide additionnal protection for h7.
|Jan-07-09|| ||notyetagm: <Once: ... Those who spotted the full line in an instant humble me.>|
Took me about two minutes to see all the lines, the failure of the defense 25 ... ♖g8-g7 to 26 ♖a1-h1 and the <KNIGHT FORK> of the <UNDEFENDED> Black b6-queen in the variation 25 ... ♔h8-g7 26 ♖h2x♘h7+ ♔g7-f8 27 ♘f6-d7+.
|Jan-07-09|| ||TheaN: <Kasputin: Isn't it fair to say that it is only impossible if black prevents it? If white has the opportunity to sac the knight for the 2 centre pawns, then maybe that is what white should do. Well I guess it hardly matters as Na4 can be played in any case.>|
That is fair, and that is what I said, although I was not very clear in my posts about this point. In my first two posts I already mentioned this, only I said <Re8> instead of <Rd8>: only if Black protects d5 with Rd8 White will not have this extremely easy simplification. After Rd8, the Rook is wrongfully placed, and the Knight can get back into play easily.
|Jan-07-09|| ||TheaN: So my second post should read this:
<TheaN: 3/3 (100%)
Fair enough: my last line should read 'winning three pawns'. That analysis was only partly correct: after 28....Rd8, 29.Na4 seems definitely the best move, as Nxd5 will be impossible for quite a while.>
|Jan-07-09|| ||YouRang: After the knight fork <27.Nd7+ Ke7 28.Nxb6 Rb8 >|
I am also a bit more attracted to 29.Nxd5 exd5 30.Bxd5+ here, picking up a couple central pawns and activating my bishop with attack, rather than 29.Na4, which clings to being up a knight (however poorly placed) and leaves my bishop rather cramped.
But in the long run, both plans win.
|Jan-07-09|| ||beenthere240: <Zwugzang67>. After 24 Nf6 black might just nobble the white queen...gxh5 (...Rg7 isn't quite as "forced" as you might think). Next, 25 Rxh5 and only then Rg7 and it doesn't look great for white.|
|Jan-07-09|| ||ZUGZWANG67: Oops ! :0(|
|Jan-07-09|| ||ZUGZWANG67: Sorry about this one, guys ! :0)|
|Jan-07-09|| ||ruzon: Black really helped White out here with 22...♘xf4+ and 23...g6. Had he played those moves earlier, he maybe could have held on:|
20. ... ♘xf4
21. gxf4 g6
22. ♕h6 ♖g8
23. ♖h1 ♖g7
24. ♖h2 ♔g8
25. ♖ah1 ♔f8
but the truth is that he was in trouble as early as 9. e5.
|Jan-07-09|| ||xrt999: < sfm: So, it appears that Black could not play 15.-,Bxg5 and simply continue with a slow advance on the queen's wing. Where's the decisive mistake? >|
1.Working backwards, It appears that after 20.Kg2, I cant find a way for black to defend, and CM actually suggests the line involving ...Nxf4 losing the knight as the best option for black. I also looked at 20...Re8 which just loses outright.
2.CM suggests 16...Nd4 17.Qd2 Rfe8 18.c3 bxc3 19.bxc3 Nc6 is equalizing for black at 10 plies, attacking the e5 pawn (and d3) and kicking white's queen of the d1-h5 diagonal.
3.I asked myself is there any way for black to continue by avoiding 15...Bxg5 to preserve the h-file? I didnt find any other games in the CM database with this exact position, but moves I looked at were 15...h6 and 15...g6 which both lose to 16.Nxd5. The only other option I looked into was 15...d4 which CM says is 0.19 at 10 plies. CM still thinks the best move is 15...Bxg5 though, as it leads to the second line which favors black as in 2 above.
4.Instead of 17...Ne7, CM suggests 17...Rfe8 leaving black the option of 18...Nd4, attacking c2 threatening to fork the rooks. It also guards f3, preventing Kg2 and keeping white from developing the open h file. This knight is suprisingly hard to kick off d4 and temporarily stops white's development.
5.Lastly, the move I looked at is 8...0-0, that is to say, black is allowing white to play the central push 9.e5, where the pawn sits for the rest of the game like a bone in black's throat. I tend to play 8...dxe4 9.Nxe4 0-0 as black in this opening to avoid the uncomfortable 9.e5, which I find hard to deal with. From an opening standpoint, I am sure there is someone more qualified to explain which is better and why.
So, from my perspective, white's e pawn and the open h-file win the game, so black's goal in this opening would be to try to defuse these 2 strengths.
|Jan-07-09|| ||fouard: 24 Qxh7+ forces Nxh7. 25 Nf6 leaves black helpless to the mate threat at h7. If 25...Rg7 26 Rah1 is mate in 2. And if 25...Kg7 26 Rxh7+ Kf8 27 Nd7+ Ke7 (or Ke8) 28 Nxb6. Black has won a piece and a pawn, and has control of the h-file, and far more active pieces. Last but not least, the knight is not trapped, as often happens when a player thinks he has won material deep in enemy territory.|
|Jan-07-09|| ||OBIT: <YouRang> laments that Black's threat to capture the queen kinds of telegraphs the sacrifice. Actually, though, this threat is needed to make the sacrifice necessary for the forced win. For example, put the queen on h4, and I'd say best is 24. Nf6. With the f-pawn unable to move, mate is forced: 24...h5 (or 24...Rg7 25. Rah1 h5 26. Qxh5+) 25. Bxh5 forces mate, e.g. 25...Kg7 26. Bf3 followed by Qh6.|
As for some of the other posts I read here, uh, gee... you sac the queen to force an Arabian mate, except there is no forced mate. It's darn fortuitous that knight fork to skewer the queen falls out of the sky at the end of this combo. Put the Black queen on c6 instead of b6, and the "obvious" 24. Qxh7 leaves you dead lost after 24...Nxh7 25. Nf6 Kg7.
|Jan-07-09|| ||YouRang: <OBIT: <YouRang> laments that Black's threat to capture the queen kinds of telegraphs the sacrifice. Actually, though, this threat is needed to make the sacrifice necessary for the forced win. For example, put the queen on h4, and I'd say best is 24. Nf6. >|
A good point.
|Jan-07-09|| ||MarbleSkull: Yeah, this puzzle must be easy, if it's one of the three I've gotten so far.|
|Jan-07-09|| ||NakoSonorense: Easy easy easy. Not hard at all to see the open file with the possibility of aligning the Q + 2R and attack the weak h-pawn.|
The Knight is also a key component, of course.
|Jan-07-09|| ||TheBish: A Stukopin vs B Hasenohr, White to play (24.?), "Medium/Easy" (2 stars)
Candidate moves: 24. Qh6, 24. Qxh7+
These are the only two moves I really considered (given that the queen is attacked). I assumed this was another queen sac (being a puzzle), but of course you can't assume anything!
24. Qh6 is good enough to win a pawn, forcing 24...f5 (or f6) to defend h7: 24. Qh6 f5 25. gxf6 (or 24...f6 25. Nxf6). Otherwise, this occurs: 24. Qh6 Rg7 25. Nf6, and Black is helpless to stop mate, e.g. 25...c4 26. Rah1 cxd3 27. Qxh7+! Nxh7 28. Rxh7+ Rxh7 29. Rxh7 mate. Amazing! Black's king is so bottled up, he is helpless (after 25. Nf6) to stop a mate four moves later. But, with best defense, this only wins a pawn.
On the other hand, crushing is 24. Qxh7+!!. After 24...Nxh7 25. Nf6 Rg7 26. Rah1, and no matter what he does, Black can't stop mate in two, starting with 27. Rxh7+. So, Black may want to try 25...Kg7, but will lose a piece (and soon the game) after 26. Rxh7+ Kf8 27. Nd7+ K(any) 28. Nxb6, regaining the queen and thus netting a knight. Very instructive tactic! It all works, thanks to Black's queen being on the fork-friendly square b6.
< Earlier Kibitzing · PAGE 3 OF 3 ·