The kingside attack coupled with the advance of the passed pawn should win for white. I must add that whites way of winning is indeed very nice.

<obender71 27 ... h5!
Pity, it was a nice puzzle.>

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Beliavsky vs Gulko, 1990

White to move, (24. '?').

First of all, you should probably read all of the other posts, (I have!); it seems to me to be a waste of time to (continuously) repeat what has already been stated.

I spent over an hour on this one last night, (blowing up the diagram, and printing it out, then setting up the position on my set).

I won't write down everything I thought about. (It would take a lot of time and bore you to death, I am sure.) Instead, I will just briefly summarize.

White is clearly better, pieces on great squares, a protected passed pawn. However, how to make progress?

At first, I looked at 24.BxP/f5, gxf5; 25.Bh6. Howver, this goes nowehere, (if Black plays correctly, 24...Bf6). I looked at many other false tries as well, and eventually settled for 24.h4, trying to degrade Black's castled position (with h5, and hxg6, etc.)

I did look at 24.Nc7, but I ran up against a brick wall here. 24...RxR/e1+; 25.Qxe1, h6; as <anatoly21> and <Jimfromprovidence> pointed out. I also got as far as the game continuation 27...Qd8. Then I thought White would exchange Queens, win the Black Bishop on a8. Then what? (I totally underestimated Qf4+, not seeing the mating web that the BK was in.)

Beliavsky vs Gulko, 1990 (24.?)

White to play and win.

Material: Even. The Black Kg8 has 1 legal move, along the diagonal to f7. The White Re1 x-rays Re8 through the White Ne6, raising possibilities of a discovered attack. The Ne6 also can fork the loose Ba6 and Re8 from c7, thereby burdening the Black Qd7. The White battery Qc1 and Bg5 already have a strong grip on the dark squares around Kg8, but to threaten Kg8, White must spread his attack to light squares. The Qc1 also seems to embarrass the loose Ba6 with Qc1-a3. The White Kg1 is secured from check but vulnerable to back-rank mate.

Candidates (24.): Qa3, Bxf5

[24.Qa3 Na5, threatening 25…Bxc5. The Re1 also pins Ne6 to a mate threat at e8.]

I have spent over half an hour on this. My best effort: 24 Bxf5 gxf5 25 Bh6 Nd6 26 Qg5+ Kf7 27 Qh5+ Kg8 28 Re3 and I cannot see a good defense for Black: perhaps 28 ...Rxe6 giving back material is necessary. Meanwhile I have perpetual check if on arrival at the position I can spot a good counter to 28 Re3 (this assumes, of course, that 25 ...Nd6 is Black's best reply]. Time to check.
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Wrong again. Interestingly, Nc7 (the first move I considered) was right after all, I saw the first three moves of this forcing line but missed 27 Bd2 and thought White simply ran out of attacking ideas.

{D86: Exchange Grünfeld: Classical Line (7 Bc4)

1. d4 Nf6 2. c4 g6 3. Nc3 d5
4. cxd5 Nxd5 5. e4 Nxc3 6. bxc3 Bg7 7. Bc4 O-O 8. Ne2 Nc6 9. O-O b6 10. Bg5 Bb7 11. Qd2 Qd6 12. Rad1 Na5 13. Bd3 c5 14. d5 e6 ♗lack threatens to win material: e6xd5 15. c4 ♗lack's piece can't move: a5 (15. Bf4 Qd7 ) 15... Ba6 ♗lack threatens to win material: ♗a6xc4 (15... Rae8 16. Bf4 e5 17. Bg3 ) 16. Qc1 (16. Qc2 e5 ) 16... exd5 (16... Rae8 17. Rfe1 ) 17. exd5 Rae8 ( 17... Qd7 18. Rfe1 ) 18. Ng3 (18. Rfe1 Qd7 ) 18... Qd7 19. Rfe1 (19. Rde1 f5 ) 19... f5 White has an active position (19... f6 20. Bf4 ) 20. Ne2 (20. Nf1 Bb7 ) 20... Nb7 (20... Qa4 looks like a viable alternative 21. d6 Qd7 ) 21. Nf4 Rxe1+ (21... Nd8 $5 should not be overlooked) 22. Rxe1 Re8 23. Ne6 (23. Rxe8+ Qxe8 24. Ne6 ) 23... Bh8 ? ( 23... Nd6 ) 24. Nc7 Deflection: c7 Rxe1+ (24... Qxc7 25. Rxe8+ Discovered attack (25. Rxe8+ Deflection)) 25. Qxe1 Qxc7 leading to a quick end (25... h6 26. Bf4 g5 ) 26. Qe8+ Kg7 27. Bd2 Qd8 (27... Bxc4 does not solve anything 28. Bxc4 Qd8 29. Qe5+ Qf6 30. Qc7+ Qf7 31. Bh6+ Kf6 32. Bg5+ Kg7 33. Qe5+ Kg8 34. Qb8+ Kg7 35. d6 Qxc4 36. Qxb7+ Qf7 37. Qxf7+ Kxf7 38. d7 ) 28. Bc3+ Kh6 29. Qe3+ (29. Qxh8 is impossible Qxh8 30. Bxh8 Nd6 ) 29... Qg5 30. f4 (30. Bxh8 is a weaker possibility Qxe3 31. fxe3 Nd6 ) 30... Qg4 (30... Qxg2+ hoping against hope 31. Kxg2 Bxc3 32. Bxf5 Bd2 33. Qxd2 gxf5 ) 31. Bxh8 Qd1+ 32. Bf1 Nd6 33. Qh3+ (33. Qe7 Nf7 34. Qxf7 Qe1 35. Qg7+ Kh5 36. Qxh7+ Kg4 37. Qxg6+ Kxf4 38. Qh6+ Ke4 39. Qe6+ Kf4 40. Qxe1 Kg5 41. Qg3+ Kh6 42. Qg7+ Kh5 43. Be2+ Kh4 44. Qg3#) 33... Qh5 34. Qc3 Ne8 35. d6 Deflection: g7 Qd1 (35... Nxd6 36. Xg7 Deflection (36. Qg7# Mate attack)) (35... -- 36. d7 Mate threat) 36. Qh3+ (36. Qh3+ Qh5 37. d7 Qxh3 38. gxh3 Nf6 39. d8=Q Bxc4 40. Qf8+ Kh5 41. Qxf6 h6 42. Bxc4 g5 43. Bf7+ Kh4 44. Qxh6#) (36. d7 Nf6 37. Bxf6 Qd4+ 38. Bxd4 g5 39. d8=Q gxf4 40. Qf6+ Kh5 41. Qh3#) 1-0

I think the best variations for both sides ends up being:

26.Bf4 g5 27.Be5 Qe7 28.Bc3 Qxe1+ 29.Bxe1 Bxc4! (getting at least a pawn for the bishop) 30.Bxc4 Nd6

Now White has either Bb3 or Bd3

31.Bb3 Kf7 32.Ne6 Bb2

31.Bd3 Kf7 32.Ne6 Bb2

The endgame looks surprisingly drawn to me. Black has c4 and b5 up his sleeve, mobilizing the black pawns; White's d-pawn is immobile because of Black's king; and Black has no easy targets for the extra piece to focus on.

In response to the game continuation 24 Nc7! Rxe1+ 25 Qxe1 Crafty continues 25...Qxc7 (as in the game) 26 Qe8+ Kg7 27 Bd2 Nd6! 28 Bc3+ (what else?) Kh6 29 Qxh8 Qe7 30 Bd2+ (if 30 h4 Bxc4!) g5 31 h4 Qg7

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and Black appears to be holding the ending (the c4 pawn falls).

In the above position, playing White, I could not find anything better than 32 Bxg5+ Kg6 33 Qxg7+ Kxg7 34 Bf4 Bxc4 35 Bxc4 Nxc4 36 Kf1 Kf6 37 Ke2 b5 38 Kd3 Nb2+ 39 Kc2 Na4 40 Kd3

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... Nb2+ and we are repeating moves. Instead 40...Nb6 seems very dangerous even though White has 41 Bd6 Nxd5 42 Bxc5 Nf4+ 43 Kd4 Nxg2 44 Bxa7 Nxh4 45 Kc5

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In this position I cannot find a way of stopping Black's h pawn.

Here's your position after 32..Kg6.

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In a game situation, I would be very reluctant to trade off this powerfully posted knight unless I could get a clearly winning advantage with it. Given that, I'm not going to play 24. Nc7 unless I can see the combination all the way to the end. With 24. Bf4, I figure, I am threatening Nc7, forking the rook and a bishop that I see has no moves. It looks to me like Black has to move his knight in response to free his bishop. The most natural move looks like 24...Nd6?, but against that I have 25. Bxd6 Qxd6 26. Bxf5! gxf5 27. Qg5+ Kf7 28. Qxf5+ Kg8 29. Qg5+ Kf7 30. Qh5+ and wins (30...Ke7 31. Nc7+ is brutal).

Black does have better than 24...Nd6; for example, 24...Nd8 seems playable to me. I think White is definitely better, but the win is not so clear. So, anyway, that's my latest installment of Think Like a Club Player.

* * * * *

There is no obligation for white to continue with 33 Qxg7+. Instead, attacking the knight with either 33 Qd8 or Qb8 looks awful for black.

I still think you give black too much possibility for a draw with this line.

After h6, I would immediately trade off queens with Qe7 Qxe7, Bxe7

You end up losing your passed pawn but you gain a whole piece from it and should be able to win the end game with a knight for white vs pawn for black. Play would probably continue

...Kf2, d6 Be5, Nxa6 Nxe6, Bxe6 Bxe6

White to play (24?) "Difficult"

Candidate moves: Qa3, Nc7

24. Qa3 Na5 25. Bd2 Bxc4 is actually good for Black.

24. Nc7! Rxe1+ 25. Qxe1 Qxc7 26. Qe8+ Kg7 27. Bd2! and now:

A) 27...Nd6 28. Bc3+ Kh6 29. Qxh8 Qe7 (29...Bxc4 30. Qf6! Kh5 31. Bd2 h6 32. g4+ Kxg4 33. Qxg6+ Kh4 34. Qxh6+ Kg4 35. h3+ Kf3 36. Qf4#) 30. Bd2+ g5 (or 30...Kh5 31. Be2+! Kh4 [31...Qxe2 32. Qf6+ Kg4 33. Qg5#] 32. Qc3! (or 32. f4!) and mate in a couple moves.

31. g3

Prevents black's bishop from taking a strong diaganol

Now if black's king chooses to run to the queenside, simple maneuver the bishop to defend it and the king should be able to pressure black into positional concessions on the kingside since his whole queenside will be locked down

Now, black's only real option after g3 is a king move, so

31...Ke6 32. Kf1

To protect your light squared bishop and prevent the black king from invading

Now if he decides to move queenside, maneuver the bishop over and protect

There are really a couple of plans here, to move the king to d4 and sacrifice a kingside pawn to get rid of white's c4 pawn or to protect the pawn and push the g pawn now

32...Ke5 33. Ke2 Kd4 34. Kd2 f4 35. Bxg6 Kxc4 36. Bd3+ Kd4

Now black's queenside is a bit stronger but your knight is helping guard on that side still and I think it's apparent white will hold onto his knight after

37. a4

Now white has a dominant position and will win

Lets analyze the other possibility

32...g5 33. Ke3

Now what? It looks like black has a pretty solid wall of pawns heading white's way and will pull off getting the isolated c pawn and win the game

I believe black's best move from here is

33...f4+ 34. gxf4 gxf4+ 35. Kd2

It looks like the same position as before but with black having isolated all of white's pawns and blocked them with his own

35...Kd4 36. f3 h5 37. h4

Black cannot move his bishop off the diaganol without white's knight coming into the game and slaughtering black

37...Be5

Now black is completely out of moves... Stuck moving the bishop back and forth on the diaganol... but it appears the same is true of white until you see

38. Bg6

You sacrifice a pawn

38...Kxc4 39. Bf7+ Kd4 40. Bxh5

Black is now forced to let your knight back in the game

40...Be7

Now where do we want to put our knight? Nc7 looks active but it's bad, so

41. Nb8 Bxh4 42. Nc6+ Kd5 43. Nxa7

Black could not avoid the fork. Moving the king allows white to give a bishop check and a passed h pawn.

Now if Kb4? Be8 and it's all over after Kc2 and the knight maneuvering his way to eat the rest of black's pawns