White to move. Can you find the winning pattern?
8/8/8/8/5K2/6R1/7k/5b2 w – – 0 7
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White to move. Can you find the winning pattern?
8/8/8/8/5K2/6R1/7k/5b2 w – – 0 7
the pattern goes like this:
first of all this is the right corner for a mate. with a darksquared bishop black has the defence resources of stalemate.
(1)the king marches to f2.
(2)in the right moment (with waiting moves on the third rank if needed, with the purpose of not letting out the black king out of the corner) the rook moves along the f-file (or any other file), attacking the black bishop and threatening mate.
(3)the bishop moves to escape the capture covering the mating squares.
(4)the rook gives check on the h-file.
(5)the bishop covers the check moving to h3.
(6)the rook makes a waiting move on the h-file.
(7)black king moves to h1.
(in the wrong corner black has not this move and so ensures the stalemate and draw)
(8)rook captures bishop and gives mate.
a possible line:
(1)
1.Kf3 Bd3
2.Kf2 Bc2
(2) , (3)
3.Rc3 Bb1
(black may not find time for Kh3, for instance if white moves immediately along the g-file the king can escape. white must combine his mating threats with an attack on the bishop, not giving time for Kh3)
4.Rb3 Ba2
5.Rb2 Bd5
(the bishop has been driven out of the shelter of the first three ranks, now can come the double attacks, attacking the bishop and also threatening mate, not giving black time for Kh3)
6.Rb5 Bf7
(covering h5)
7.Rb7 Bg6
(covering h7)
8.Rb6 Bf5
(the darksquared h6 cannot be covered)
(4) – (8)
9.Rh6+ Bh3
10.Rh8 Kh1
11.Rxh3++
My vision
1. Kf3!! wins after
1. … Kh1
2. Kf2 Kh2
3. Rg8 Bh3
4. Rh8
or
1. … Bf3
2. Kf2 Bc8
3. Rg8 Bh3
4. Rh8 same position and white mates black in the next move.
1.Kf3 B moves
(if Kh1,Rg8 wins)
2.Kf2 and now if 2…Bf1,
3.Rg8 Bh3
4.Rh8
or if 2…Be2
3.Rg8 wins the bishop
or if 2…B to c4, b5 or a6, then the rook moves up the G file attacking the bishop and threatening mate
There are better defenses for black:
1.Kf3 Be2+
2.Kf2 Bd1
3.Rg1 Bc2 (Be2 4.Rg8!)
4.Rc1 Bd3
Now the bishop uses the three squares d1, c2 and b3 to escape of the rook.
How to proceed for white?
Ok, here comes another pattern to help:
5.Rd1 Bc2
6.Rd2 Bb1
7.Rb2 now the bishop has to leave the first three ranks (7…. Bd3/e4? 8.Ke3+ wins the bishop)
7…. Bf5! (Bg6 8.Rb6!, Bh7 8.Rb8!)
8.Rb5 Bg4!
9.Rb4 Kh3! and now?
I can’t really add anything more to the first comment by anonymous other than to note that the correct corner is easily identified by the color of the squares f2/g3 (they must not be the color of the bishop as these are squares that must be open to white’s king).
Jean-Claude Schmidig:
Your third move doesn’t follow the correct prescription that the first Anonymous poster gives:
1. Kf3 Be2+
2. Kf2 Bd1
3. Rg3 would be the correct plan.
Now Be2 and Bd3 lose the bishop immediately, and Bc4, Bb5, and Ba6 allow the pattern given by the first anonymous. Thus:
3. … Bh3
4. Rg8 any move
5. Rh8 and after Black’s 5th move the bishop will be on h3 and the king on h1 or h2. If the king is on h1 then Rxh3 is mate if it is on h2 then as in the first posters idea the rook moves along the h file to force Kh1. Oops I suppose black’s fifth move could also be Bh5 or Bh7 which is obviously followed with RxB#.
3. … Bg2
4. Rg3 Bf1 or Bh3
5. Rg8 any move
6. Rh8 and white mates as above.
Other lines after 3. …Bg2 4. Rg3
4. … Bf3 just loses the bishop
4. … Be4 or Bc6 allow the pattern given by the first poster
4. … Bd5 however, demonstrates a slight wrinkle to the idea of the first poster:
5. Rg5 Bf7 (denying the checking square h5)
6. Rg7 repeats the pattern of threatening mate and attacking the bishop, and now the bishop can’t safely cover the checking square so it is over.
Similarly, on 4. … Bb7
White has to play Rg7 and then Rg4 if black covers h7 with the bishop.
Jim Lin,
3.Rg3?? (the rook already stands on g3)
Your given lines are not coherent. Black tries to use the squares b1, c2, d3 unless the rook goes to b2 after that Bf5 is a good replay.