Black cannot lose. A draw is there for his asking.
1…..Rg8! freezing the BB with the h pawn immobile. B can only move King.
2.Kf/g/h2. Rxg5. 3. hxg5. Kf5 followed by 4. K any.Kxg5/6 draw as Black cannot queen lone h pawn.
2. Kh3. Rxg5. 3. hxg5. Kf5. 4. Kh4. Kg6! 5. Kg/h3. Kxg5 draw as B cannot queen lone h pawn.
Let us next try a win for B.
This is a famous endgame, analyzed by many theorists, and there is no clear
agreement what is the best winning strategy. Rubinstein won it in a brilliant
way but both players made numerous mistakes in the middle.
It is fun to go deeper into some of those variations but these are, in fact, purely
theoretical discussions, very far from “must know endgame” (it is as much fun as
solving some “checkmate in 2” problems). I used to play
tournament chess for 15 years and never, ever encountered an endgame of
this kind (ie R vs B and 2 h (or a) pawns. So, if you cannot really find a solution
do not feel bad, because there is hardly any clear solution. It is definitely
not an endgame you “must know”. :-)))
Thanks for the link to the game! It was enlightening playing through that again. Yes, both players made a lot of errors. I found it interesting that Salwe allowed himself to play the king so far up the board, rather than keep the king near the queening corner; what turned out to be the ultimate mistake that cost him the game. Once he made that error, it seems Rubinstein’s play, while a bit inaccurate, never returned the favor afterwards.
Philosopher 55 is right- this is a very famous endgame. It is one I first studied more than a quarter century ago, though the analysis available to me at that time was a bit faulty. One of the faults in some of the more ancient analyses can be actually be found in the line that Rajan above provided, which I will clean up by putting in the proper format:
1. ………..Rf3!? (a winning move)
2. Kg2 Rb3? (a drawing move)
3. Kf2! Kf5
Now, it looks for all the world that black has accomplished a winning position here- he has opened the door to g4 for the black king, and the white king is trapped below the 3rd rank. However, this isn’t sufficient to win. Though I am ignoring variations in the following, this is just for demonstration purposes that Rajan’s idea is insufficient. After 2. …Rb3, every move for white makes in this line is a drawing move as long as white makes no subsequent mistakes:
8. …………Re5 (planning a double attack on Bg5)
9. Kd1
Or Kd2. Even Kc2 is a draw here. Continuing:
9. …………Kg4
10. Kc1
Here, white draws with Bf6, Kc2, and Kd1. I just picked Kc1 because it looks the most losing:
10. ……….Rg5
11. hg5 Kg5
12. Kd1
And one should be able to see that the black king cannot keep the white king out of the corner just by counting the moves, however, for demonstration:
12. ………..Kg4
13. Ke1 Kg3
14. Kf1!
Remember, the black king can’t allow himself to get trapped in front of the pawn, so even 14. …Kh2 won’t help black win. In short, it does black no good to drive the white king all the way over the c-file and then try to win with a sacrifice at g5. In my next comment, I will try to give one the flavor of how to go about winning this.
So, how can white win this. The basic idea is the same in all the important lines. This is not going to be a comprehensive analysis- for that you need to spend the next year studying the Nalimov Tablebase variations (seriously, a year).
1. ………Kd3
There are other winning moves here- basically, any move that doesn’t allow white to play Kf2. Kd3 is simply the most direct:
2. Be7 Rf7
3. Bg5 Ke2
The first part of the plan is now accomplished- black has taken f2 away from white’s king using the king rather than the rook. White can delay things a move here with Bh6, but the endpoint is going to be same even if white plays any other move 1st:
4. Bh6 Rf3
5. Kg2 Rd3
The white king has been pushed back a rank, so black is most efficient keeping the rook on the third rank for the moment- Rd3 is a waiting move:
6. Bg5 Rd4 (now positioning the rook to come to g4)
7. Bf6 Rg4
8. Kh3 Kf3
The threat now is to check from g3. There are longer lines white can force here, but let’s skip those for now:
9. Bg5 Rg3
10. Kh2 Kg4
11. Bd8 Re3 (threatening to push the king back with Re2+)
12. Kg2 Re2
13. Kg1 Kh3 (slightly more accurate than Kg3)
14. Kf1 Re8 (attacking the bishop)
15. Bg5
Again, white can delay things a bit with a move like Bc7, but you will eventually end up in the same basic place since black just takes the pawn immediately- the line with 15.Bg5 is the more critical one. Continuing:
15. ……….Kg3
This is zugzwang. The white king cannot move without allowing mate on the next move, and the bishop cannot continue to protect the h-pawn from the king without allowing either its own direct capture on e7 or d8, and will get pinned and captured if it comes to f6.
Basically, white cannot prevent black from achieving this kind of position- the white king cannot avoid going to the f-file at some point, otherwise black will just mate him in the corner or on h3 with the rook in the corner.
It is left as an exercise to work through the other defenses.
And just one last thing before I let this thread go- probably the most important variations in the line above arise with White attempting to prevent the check from g3- at move 8, white can try 8.Be5 covering g3. Black can use rook maneuvers and attacks on the bishop along with the mate threats to reach the same zugzwang position above:
8. Be5 Re4 (attacking the bishop)
9. Bc3 Re3 (attacking the bishop again)
10. Bd2
Here, white is both preparing a return of the bishop to g5 and covering the e1 square, however, black foils these plans with another attack on the bishop:
10. …………Rd3
11. Bg5 Rd1
Now black uses the mate threat to force the white king to give up the h3 square and the cover on the g4 square:
12. Kh2 Kg4
The rest more or less follows what I showed above.
And FYI, the above is why it was important to not allow the white king access to the f-file too early- if he got there early, black could defend by retreating to safety on the e-file in the critical lines. That is why I took the trouble to show you why the sacrifice at g5 was never going to work.
Thank you. The real insight into understanding this is that white can easily defend from the 1st and 2nd rank without black having to worry about a mate threat with the rook and king- the bishop from g5 controls f4, e3, and e2 already, and can control others from f6, too. To make progress, black had to win the h-pawn outright. One just had to imagine the position that forces the bishop away from that diagonal, which means taking away d8, e7, and f6 at the right juncture with the white pawn under attack by the black king- a black rook at d7 or e8 with a white king on an open f-file can do that. The only question is how to arrange that by force.
Black cannot lose. A draw is there for his asking.
1…..Rg8! freezing the BB with the h pawn immobile. B can only move King.
2.Kf/g/h2. Rxg5. 3. hxg5. Kf5 followed by 4. K any.Kxg5/6 draw as Black cannot queen lone h pawn.
2. Kh3. Rxg5. 3. hxg5. Kf5. 4. Kh4. Kg6! 5. Kg/h3. Kxg5 draw as B cannot queen lone h pawn.
Let us next try a win for B.
1. Rg8
2. Kh3 Rxg5
3. hxg5 Kf5
4. g6 Kxg6
5. Kh4 Kh6
6. Kh3 Kg5
7. Kg3 h4+
8. Kh3 Kh5
9. Kg2 Kg4
10. Kh2 h3
11. DRAW so long the white King cannot be chased from h1
It’s a Win for Black, the idea is to run away the White king and block him in the c file
Thereby not able to defend the stalemate
1) Rf3+ Kg2
2) Rb3 Kf2
3) Kf5 Kg2
4) Kg4 Kf2
5) Rb2+ Ke1
6) Kf3 kd1
7) Re2 kc1
By blocking the White King within the C file, and then after exchange of Rook for Bishop and Pawn
Black has an extra pawn to become queen.
Just Black making sure, that the Black King is present in g2 before white king comes there, will win the game for black.
This is a famous endgame, analyzed by many theorists, and there is no clear
agreement what is the best winning strategy. Rubinstein won it in a brilliant
way but both players made numerous mistakes in the middle.
Some exemplary notes can be found there:
http://www.chessgames.com/perl/chessgame?gid=1306042
or there
http://todesursachesport.de/material/endgame_corner/mueller07.pdf
and in other places.
It is fun to go deeper into some of those variations but these are, in fact, purely
theoretical discussions, very far from “must know endgame” (it is as much fun as
solving some “checkmate in 2” problems). I used to play
tournament chess for 15 years and never, ever encountered an endgame of
this kind (ie R vs B and 2 h (or a) pawns. So, if you cannot really find a solution
do not feel bad, because there is hardly any clear solution. It is definitely
not an endgame you “must know”. :-)))
Thanks for the link to the game! It was enlightening playing through that again. Yes, both players made a lot of errors. I found it interesting that Salwe allowed himself to play the king so far up the board, rather than keep the king near the queening corner; what turned out to be the ultimate mistake that cost him the game. Once he made that error, it seems Rubinstein’s play, while a bit inaccurate, never returned the favor afterwards.
I am not sure of the result from my analysis. But Nalimov”s tablebase predicts mate in 48 moves.
Philosopher 55 is right- this is a very famous endgame. It is one I first studied more than a quarter century ago, though the analysis available to me at that time was a bit faulty. One of the faults in some of the more ancient analyses can be actually be found in the line that Rajan above provided, which I will clean up by putting in the proper format:
1. ………..Rf3!? (a winning move)
2. Kg2 Rb3? (a drawing move)
3. Kf2! Kf5
Now, it looks for all the world that black has accomplished a winning position here- he has opened the door to g4 for the black king, and the white king is trapped below the 3rd rank. However, this isn’t sufficient to win. Though I am ignoring variations in the following, this is just for demonstration purposes that Rajan’s idea is insufficient. After 2. …Rb3, every move for white makes in this line is a drawing move as long as white makes no subsequent mistakes:
4. Kg2 Kg4
5. Kf2 Rb2
6. Ke1 Kf3
7. Kd1 Re2
8. Kc1
This position is still drawn. For example:
8. …………Re5 (planning a double attack on Bg5)
9. Kd1
Or Kd2. Even Kc2 is a draw here. Continuing:
9. …………Kg4
10. Kc1
Here, white draws with Bf6, Kc2, and Kd1. I just picked Kc1 because it looks the most losing:
10. ……….Rg5
11. hg5 Kg5
12. Kd1
And one should be able to see that the black king cannot keep the white king out of the corner just by counting the moves, however, for demonstration:
12. ………..Kg4
13. Ke1 Kg3
14. Kf1!
Remember, the black king can’t allow himself to get trapped in front of the pawn, so even 14. …Kh2 won’t help black win. In short, it does black no good to drive the white king all the way over the c-file and then try to win with a sacrifice at g5. In my next comment, I will try to give one the flavor of how to go about winning this.
So, how can white win this. The basic idea is the same in all the important lines. This is not going to be a comprehensive analysis- for that you need to spend the next year studying the Nalimov Tablebase variations (seriously, a year).
1. ………Kd3
There are other winning moves here- basically, any move that doesn’t allow white to play Kf2. Kd3 is simply the most direct:
2. Be7 Rf7
3. Bg5 Ke2
The first part of the plan is now accomplished- black has taken f2 away from white’s king using the king rather than the rook. White can delay things a move here with Bh6, but the endpoint is going to be same even if white plays any other move 1st:
4. Bh6 Rf3
5. Kg2 Rd3
The white king has been pushed back a rank, so black is most efficient keeping the rook on the third rank for the moment- Rd3 is a waiting move:
6. Bg5 Rd4 (now positioning the rook to come to g4)
7. Bf6 Rg4
8. Kh3 Kf3
The threat now is to check from g3. There are longer lines white can force here, but let’s skip those for now:
9. Bg5 Rg3
10. Kh2 Kg4
11. Bd8 Re3 (threatening to push the king back with Re2+)
12. Kg2 Re2
13. Kg1 Kh3 (slightly more accurate than Kg3)
14. Kf1 Re8 (attacking the bishop)
15. Bg5
Again, white can delay things a bit with a move like Bc7, but you will eventually end up in the same basic place since black just takes the pawn immediately- the line with 15.Bg5 is the more critical one. Continuing:
15. ……….Kg3
This is zugzwang. The white king cannot move without allowing mate on the next move, and the bishop cannot continue to protect the h-pawn from the king without allowing either its own direct capture on e7 or d8, and will get pinned and captured if it comes to f6.
Basically, white cannot prevent black from achieving this kind of position- the white king cannot avoid going to the f-file at some point, otherwise black will just mate him in the corner or on h3 with the rook in the corner.
It is left as an exercise to work through the other defenses.
And that first sentence should be “how black wins”.
And just one last thing before I let this thread go- probably the most important variations in the line above arise with White attempting to prevent the check from g3- at move 8, white can try 8.Be5 covering g3. Black can use rook maneuvers and attacks on the bishop along with the mate threats to reach the same zugzwang position above:
8. Be5 Re4 (attacking the bishop)
9. Bc3 Re3 (attacking the bishop again)
10. Bd2
Here, white is both preparing a return of the bishop to g5 and covering the e1 square, however, black foils these plans with another attack on the bishop:
10. …………Rd3
11. Bg5 Rd1
Now black uses the mate threat to force the white king to give up the h3 square and the cover on the g4 square:
12. Kh2 Kg4
The rest more or less follows what I showed above.
And FYI, the above is why it was important to not allow the white king access to the f-file too early- if he got there early, black could defend by retreating to safety on the e-file in the critical lines. That is why I took the trouble to show you why the sacrifice at g5 was never going to work.
Damn, I am so accustomed to “white to win” problems. that first sentence should be “white could defend”. Oh, to have the ability to edit a comment!
Well done, Yancey. If it’s possible to make such a fuzzy thing
more comprehensible and clear, you gave a good shut. Bravo.
Thank you. The real insight into understanding this is that white can easily defend from the 1st and 2nd rank without black having to worry about a mate threat with the rook and king- the bishop from g5 controls f4, e3, and e2 already, and can control others from f6, too. To make progress, black had to win the h-pawn outright. One just had to imagine the position that forces the bishop away from that diagonal, which means taking away d8, e7, and f6 at the right juncture with the white pawn under attack by the black king- a black rook at d7 or e8 with a white king on an open f-file can do that. The only question is how to arrange that by force.