i think, white can win with 1. h7 b2 2. Kh6 b1Q 3. g7# if 2. Rc6, then 3. Rf8# if 1. Kg7, then 2. Rf7+ Kh8 3. Kh6 Rc6 4. Rf8# or 3. b2 4. g7# greets, jan
White wins with h7, threatening the ‘a’ black pawn with the rook either from the first rank or from the ‘a’ file. The advance of the ‘b’ black pawn interferes with the a1-h8 diagonal, allowing g7. So: 1. h7 .. Kg7 2. Rf7+ .. Kh8 3. Ra7 .. a1/Q 4. Rxa1 .. b2 5. Rb1 .. Rb8 6. Kh6 .. Rb6 7. Rxb2
There are only three possible first moves g7, h7, and Rf7. I will take the first and third of these since they are the easy to see as wrong:
1. g7 Kg8 (Kh7? 2.Rf8 Rf8 3.gf8Q) 2. Kg6
What else? Continuing:
2. ….Rc6 (only move) 3. Kg5 Kh7 4. Rf8 Rg6 5. Kf5 Kh6 and it is over- black will queen one of his remaining pawns. Or
1. Rf7 a1(Q) 2. Rh7 Kg8 3. Rg7 Qg7 and it is over- black wins. This leaves only
1. h7! Kg7 (what else?) 2. Rf7 Kh8
And here, at move 3, is the move that isn’t obvious. Indeed, the first time through this, I was completely convinced 3.Kh6 was a clear winner, and had even written out my comment and was about to post it before I noticed I had blundered- black has a resource I overlooked the first time-
3. Kh6?? a1(Q) (Rc6?? 4.Rf8#) 4. g7 Qg7 5. Rg7 Rc6! and the rooks come off the board and black’s remaining pawn can’t be stopped. With a1(Q) a threat covering g7, white must play
3. Ra7!
And, now, the threat of Kh6 and g7 is unstoppable as the a-pawn cannot queen and cover g7. All I see here for black are delays involving material sacrifice like Rc5 followed by Rh5, or a1(Q). The longest such line seems to me to be
Returning the rook to the f-file so that it can check from f7 if black tries Kg7 again:
5. …..b1(Q) (shorter mates else) 6. Rb1 Kg7 7. Rb7 Kf6 8. g7 Rc5 9. Kh6 Rc1 (one last trick) 10.Rb6 and white will queen the g-pawn without further delay.
The other choice is 1 g7+, but this loses as follows:
1 g7+? Kg8!
And not 1 … Kh7? 2 Rf8 Rxf8 (1 … Rc5+, 2 Kg4, and Black can’t promote the Queen because of Rh8+, forcing mate in a few moves) 3 gxf8=Q a1=Q, 4 Qf7+, winning the pawn, although the position is still a draw.
With the actual move, 2 Rf8 won’t work, as Black’s King also guards the f8 square.
2 Kg6 Rc3+ 3 Kg5 Kh7 4 Rf8 Rg6+
The point of the maneuver. Black gets to the pawns via another avenue.
5 Kf5 Kxh6
A bit better than 5 … Rxg7, 6 hxg7 Kxg7, which also wins.
6 g8=Q Rxg8 7 Rxg8 a1=Q
And Black wins easily.
1 h7! Kg7
Black can forestall matters for a few moves by 1 … a1=Q, but to no avail.
2 Rf7+ Kh8 3 Ra7!
The immediate 3 Kh6?? doesn’t work, as 3… a1=Q, 4 g7+ Qxg7, 5 Rxg7 Rc6+, 6 Rg6 Rxg6+, followed by promoting the b pawn.
Now White threatens Kh6.
3… a1=Q
The only move the prolongs the game.
4 Rxa1 b2 5 Rf1
Of course, 5 Kh6?? still won’t work, due to 5 … a1=Q, blocking the Pawns move to g7.
5 … b1=Q
5 … Rc1 leads to a mate in two by 6 Rh8+ Kg7, 7 h8=Q#
6 Rxb1 Rc6
Loses quickly, but nothing else is good. 6 …Kg7 7 Rb7+ (The chess engines found that 7 Rb5 mates a move sooner) Kf6, 8 g7 Rc5+ 9 Mh5 Rc2 10 Rb6+ etc.
With the move, Black sets one last trap.
7 Rb8+
If White plays the careless 7 Kh6? , then 7… Rxg3+! draws.
win…h7
1.h7 Kg7 2.Rf7+ Kh8 3.Ra7
i think, white can win with
1. h7 b2
2. Kh6 b1Q
3. g7#
if 2. Rc6, then
3. Rf8#
if 1. Kg7, then
2. Rf7+ Kh8
3. Kh6 Rc6
4. Rf8#
or 3. b2
4. g7#
greets, jan
The solution is:
1. g7+ Kh7
2. Rf8 Rc5+
3. Kg4 Rc4+
4. Kf3 Kxh6
5. g8=Q a1=Q
6. Qe6+ Kg7
7. Rf7+ Kg8
8. Qe8#
White win
Sergio Marroquin
México
1.-h7 Ta8; 2.- Kh6 a1=Q; 3.- Rxa1 Rg8; 4.- hxg7=Q Kxg8; 5.- Ra8# withe win. I posted other solution, but this one is better (I think).
White wins with h7, threatening the ‘a’ black pawn with the rook either from the first rank or from the ‘a’ file. The advance of the ‘b’ black pawn interferes with the a1-h8 diagonal, allowing g7. So:
1. h7 .. Kg7
2. Rf7+ .. Kh8
3. Ra7 .. a1/Q
4. Rxa1 .. b2
5. Rb1 .. Rb8
6. Kh6 .. Rb6
7. Rxb2
or 1 .. Ra8
2. Kh6 .. a1/Q
3. Rxa1
or 1 .. b2
2. Kh6 with double threat g7/Kf8
1. h7
if
1. .. b2
2. Kh6 and 3 g7#
if rook moves from 8th row
then rf8 and h8=Q is deadly
if
1. .. kg7
2. Rf7+ kg8 and continue with Kh6 and g7
1. h7 Kg7 2. Rf7+ Kh8 2. Ra7
1. h7 Kg7 2.Rf7+ Kh8 3.Ra7
Its a win for white. Just play
1.h7 and its all over.
The mate threat is unstoppable.
If 1…. b2; 2. Kh6 and finish.
If 1…Kg7; 2.Rf7+ -Kh8 and 3. Ra7!
Win. Pawn to H7.
What about 1. h7 Kg7 2. Rf7+ Kg8 3. Ra7! b2 (closing the diagonal) 4. Kh6 with indefensible threats?
1. Rf8+ RxR
2. g7+ Kg8
3. Kg6
The immediate Rf8+ doesn’t seem to work
Rf8+ Rxf8 g7+ Kg8 gxf8(q)+ Kxf8 h7 a1(q) -+
I think it transposed from g7+ Kg8 as well
Rf7 looks like it can secure at least the draw. But white does have one tempo to use
h7 b2 Kh6 (now the b2 pawn blocks the queen on a1 and a queen on b1 doesn’t help since g7#) Rf7 g7+ Rxg7 hxg7+ Kg8 Rf8#
Black can deflect the rook after h7 but that only loses his counterplay.
White wins!
Perhaps draw? I’m just guessing.
I think that this is a good chance for a win.
1 h7 (threatens Kh6 and mate) Kg7
2 Rf7+ Kh8
3 Ra7 (to prevent queening) b2
4 Kh6 a1 or b1 (Q)
5 g7#
There are only three possible first moves g7, h7, and Rf7. I will take the first and third of these since they are the easy to see as wrong:
1. g7 Kg8 (Kh7? 2.Rf8 Rf8 3.gf8Q)
2. Kg6
What else? Continuing:
2. ….Rc6 (only move)
3. Kg5 Kh7
4. Rf8 Rg6
5. Kf5 Kh6 and it is over- black will queen one of his remaining pawns. Or
1. Rf7 a1(Q)
2. Rh7 Kg8
3. Rg7 Qg7 and it is over- black wins. This leaves only
1. h7! Kg7 (what else?)
2. Rf7 Kh8
And here, at move 3, is the move that isn’t obvious. Indeed, the first time through this, I was completely convinced 3.Kh6 was a clear winner, and had even written out my comment and was about to post it before I noticed I had blundered- black has a resource I overlooked the first time-
3. Kh6?? a1(Q) (Rc6?? 4.Rf8#)
4. g7 Qg7
5. Rg7 Rc6! and the rooks come off the board and black’s remaining pawn can’t be stopped. With a1(Q) a threat covering g7, white must play
3. Ra7!
And, now, the threat of Kh6 and g7 is unstoppable as the a-pawn cannot queen and cover g7. All I see here for black are delays involving material sacrifice like Rc5 followed by Rh5, or a1(Q). The longest such line seems to me to be
3. …..a1(Q)
4. Ra1 b2 (Kg7 5.Ra7 Kf6 6.g7+-)
5. Rf1
Returning the rook to the f-file so that it can check from f7 if black tries Kg7 again:
5. …..b1(Q) (shorter mates else)
6. Rb1 Kg7
7. Rb7 Kf6
8. g7 Rc5
9. Kh6 Rc1 (one last trick)
10.Rb6 and white will queen the g-pawn without further delay.
1 h7! is the only winning move.
The other choice is 1 g7+, but this loses as follows:
1 g7+? Kg8!
And not 1 … Kh7? 2 Rf8 Rxf8 (1 … Rc5+, 2 Kg4, and Black can’t promote the Queen because of Rh8+, forcing mate in a few moves) 3 gxf8=Q a1=Q, 4 Qf7+, winning the pawn, although the position is still a draw.
With the actual move, 2 Rf8 won’t work, as Black’s King also guards the f8 square.
2 Kg6 Rc3+
3 Kg5 Kh7
4 Rf8 Rg6+
The point of the maneuver. Black gets to the pawns via another avenue.
5 Kf5 Kxh6
A bit better than 5 … Rxg7, 6 hxg7 Kxg7, which also wins.
6 g8=Q Rxg8
7 Rxg8 a1=Q
And Black wins easily.
1 h7! Kg7
Black can forestall matters for a few moves by 1 … a1=Q, but to no avail.
2 Rf7+ Kh8
3 Ra7!
The immediate 3 Kh6?? doesn’t work, as 3… a1=Q, 4 g7+ Qxg7, 5 Rxg7 Rc6+, 6 Rg6 Rxg6+, followed by promoting the b pawn.
Now White threatens Kh6.
3… a1=Q
The only move the prolongs the game.
4 Rxa1 b2
5 Rf1
Of course, 5 Kh6?? still won’t work, due to 5 … a1=Q, blocking the Pawns move to g7.
5 … b1=Q
5 … Rc1 leads to a mate in two by 6 Rh8+ Kg7, 7 h8=Q#
6 Rxb1 Rc6
Loses quickly, but nothing else is good. 6 …Kg7 7 Rb7+ (The chess engines found that 7 Rb5 mates a move sooner) Kf6, 8 g7 Rc5+ 9 Mh5 Rc2 10 Rb6+ etc.
With the move, Black sets one last trap.
7 Rb8+
If White plays the careless 7 Kh6? , then 7… Rxg3+! draws.
7 … Kg7
8 h8=Q#