In the starting position, what is white worried about?

The black rook is on an open file. That looks a bit scary at first, but it has no entry squares into white's position apart from the e3 square. And there is nothing for the rook to attack from e3. Nope, the black rook ain't frightening. It's a six year old in a Freddy Kruger mask. Ignore.

The black pawns on d4 and f4 might give you a fright. A pair of advanced passed pawns. And we can't attack either of them with our white squared bishop. But look more closely and you will see that these two pawns aren't going anywhere soon. The white king and bishop have got them nailed down. These two pawns are Michael Jackson in makeup for the Thriller video. Weird, but not frightening. "I'm not like other guys..."

The black kingside pawns are massing for an attack. We might worry about moves like f5, g5, g4 and we are getting swamped by an army of zombie pawns. In the game, Charousek succumbed to this fear and played 37. Bg4 to prevent an immediate f5. But after 37...g6, black is going to get in f5 anyway. The bishop would have been better advised to stay in the shopping mall (d1), keep the doors firmly locked and let the zombies mill around outside. It's never a good idea to get too close to a horde of zombies.

But the problem with zombies is that they are very ... slooooow.... Oh, and if you believe Michael Jackson they have a tendency to break out into choreographed dance moves. White doesn't need to worry about the black pawn avalance, because he has a zombie pawn avalanche of his own.

Hey - wouldn't that make a great film? Two opposing zombie armies fighting against each other? Instead of zombies versus humans, we could have zombie versus zombie in a fight to the ... er ... death. Again. Oops. Got distracted there.

Sometimes we need to put aside our fears and just go for it. The first move that suggested itself was 37. d6 and the more I look at the position the more I like it. Passed pawns have to be pushed. And as Dzechiel rightly says, rooks hate defending against connected passed pawns.

It turns out that the thing we ought to be worried about in this position is the black king sitting quietly on g8. If the king can get over to the white c and d pawns, then black can hold or win. And that means we need to be fast.

This seems to strongly suggest that White was winning - as does RV's R4's analysis ... yet the note says 37.d6!! is equal.

You may find that cg.com will let the debate roll for quite a while before they comment, if they comment at all.

Their rationale seems to be that this is not a puzzle, it's a position. We kibitzers will work out for ourselves the "truth" of the position - what the best move is, and what the result ought to be with best play.

You might say that this site is a sort of chess wiki, where the knowledge base is built by the users not by the moderators.

The answer to today's position seems quite clear - 37. d6 seems to be the best move. As to whether it wins or not, I think we have to work that one out for ourselves.

I sometimes think that cg.com is a little like Gandalf in the Hobbit. He starts Bilbo on the adventure and gives him assistance from time to time. But the adventure is Bilbo's and the hobbit must find his own answers to the puzzles and difficulties he encounters along the way.

Or the Lord of the Rings where half the plot seems to revolve around Gandalf going away, bad things happening, and then Gandalf returns in the nick of time to make it all better again.

Very late on the day so or even when the puzzle is off the front page.

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Rybka 4 x64:

So first we get a pawn to d6 (easy bit), but we are not actually trying to promote this pawn we are just using it to stop the king coming to e7! So the king must come across via e8, (which is currently block by a rook) or f7 (which is currently block by a pawn)! So by one simple move we have blocked the king's progress AND gained control of the dark sqaures that our LSB has no control over!

37 d6 ...

Now all thoughts of counter-attack for black vanish. (i.e. 37 ... Re3 d7 winning), so black must find a way to stop Pc4 and Pd6 from promotion, at some point Kf8 is payable, but the rook must move to allow the king into the action, so lets consider rook moves first...

37 ... Rb8 (trying to get some counter-attack going)
38 c5 Rxb2+
39 Ke1! Kf8
40 c6 Ke8
41 c7 Kd7
42 Bg4+ winning

38 ... Rd8
39 c5 Kf8
40 Bg4 Ke8 (g6 is too slow to block the c8-h3 diagonal) 41 c6 Rxd6
42 c7 Rc6
43 c8=Q+ Rxc8
44 Bxc8 winning

44 ... d3 45 Ba6 d2 46 Ke2 the black pawns are going nowhere! 44 ... Kd8 46 Bg4 d3 47 Ke1 g6 48 Kd2 f5 49 Bf3 g4 50 h3 winning

37 ... Rc8
38 Bg4 Rd8 (Rxc5 d7 winning)
39 c5 Kf8
40 c6 moving into the variation above one move earlier!

What about playing Kf8 first as the rook moves all look doomed!

37 ... Kf8
38 Bg4 Rd8
39 c5 Ke8
40 c6 g6 (Rxd6 moving into the variation above)
41 d7+ Ke7
42 c7 f5
43 Bxf5 gxf5
44 c8=Q Rxd7
45 Qc5+ Rd6
46 Qxa5 d3
47 Qd2 Rd4
48 b4 and black can resign.

What about trying to block the c8-h3 diagonal immediately?

37 ... f5
38 c5 ...

38 ... Kf8
39 c6 Ra8 (39 ... Rd8 c7 Rc8 d7 winning) or (39 ... Rc8 d7 Rd8 c7 Ke7 c8=Q winning) 40 c7 Ke8
41 Bf3 Rc8
42 Bc6+ Kf7
43 Bb7 winning

38 ... Rd8
39 Bf3 Kf7
40 c6 Ke6
41 c7 Rc8
42 Bb7 Kd7
43 Bxc8+ Kxc8
44 b4 axb5
45 a5 b3
46 a6 b2
47 a7 b1=Q
48 a8=Q+ winning

All in all I think white is winning in nearly every version. I think 37 b4 is probably okay, 37 Bg4 is probably okay too but 37 d6 seems the most forcing line!

<[37.d6 Rd8 38.c5 d3 39.Bf3 d2 40.Ke2 f5;

<(40...f6;

<(Rybka 4 - RV)> 41.Kd1! Kf7 42.c6 Ke6 43.c7 Rh8;

<(43...Rc8 44.Bg4+ f5 45.Bxf5+ Kxf5!? 46.d7 )>

44.Bg4+ Kxd6 45.c8Q Rxc8 46.Bxc8 Kc5 47.Kxd2 Kd4 48.Ke2 g5 49.Kf3 Ke5 50.Bb7 Kf5 51.Be4+ Ke5 52.Bc2 f5 53.h3! Ke6 54.h4! g4+ 55.Kxf4 )>

41.Bd5+ Kf8 42.Kxd2 Ke8 43.Be6 Kf8 44.Bxf5 Kf7 45.Ke2 Kf6 46.c6 Kxf5 47.d7 Ke6 48.c7 Kxd7 49.cxd8Q+ Kxd8 50.h4 Kd7 51.Kf3 Kd6 52.Kxf4 Kc5 53.Ke5 Kb4 54.Kd5 g6

<(54...Kxa4 55.Kc4 g6 56.b3+ Ka3 57.Kc3 Ka2 58.b4 axb4+ 59.Kxb4 Kb2 60.Kc4 Kc2 61.Kd4 Kd2 62.Ke5 Ke3 63.Kf6 Kf4 64.Kxg6 Ke5 65.h5 Ke6 66.h6 Ke7 67.h7 )>

The answer to today's position seems quite clear - 37. d6 seems to be the best move. As to whether it wins or not, I think we have to work that one out for ourselves.>

<[+3.34] d=26 37...Rd8> 38.c5 d3 39.Bf3 d2 40.Ke2 f6 41.Kd1 Kf7 42.c6 Ke6 43.c7 Rh8 44.Bg4+ Kxd6 45.c8Q Rxc8 46.Bxc8 Kc5 47.Kxd2 Kd4 48.Ke2 g5 49.Kf3 Ke5 50.Bb7 Kf5 51.Be4+ Ke5 52.Bc2 f5>

I don't get this line at all. Why wouldn't black play 40...f5, instead, preventing Bg4?

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i ran the position with the computer, and it looks like whether 40...f6 or f5 doesnt matter much, because Bg4 isnt a necessary part of whites winning plan.

after both white can play 41.Kd1 Kf7 42.c6 Ke6 43.c7 Rh8 44.Bb7 Kd7 45.Kxd2 Rxh2+ 46.Kd3 Rh8 47.Kd4 g6 48.Kd5

if in this position the pawn is on f6 black has 48...Rh5+ which prolongs the fight a bit, although its not ennough, if the pawn is on f5 black is helpless to Ba6, Bb5, Kc6

If you compare my two lines, ...f5 works out to a much greater edge for White ... apparently Rybka sees all this comimg and tries to avoid it.

after both white can play 41.Kd1 Kf7 42.c6 Ke6 43.c7 Rh8 44.Bb7 Kd7 45.Kxd2 Rxh2+ 46.Kd3 Rh8 47.Kd4 g6 48.Kd5>

Thanks for picking up the thread. So, it looks like white can get to protect c8 anyway by Bb7. I did not see that.

So, what happens if black does not play 45…Rxh2+ but plays 45…Re8 instead? (to keep the king from going after the f pawns)

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