Endgame 1

[Henk]

Skipper could not win this endgame. I can imagine that capturing the white bishop with the rook might win. So perhaps error in passed pawn bonus ?

Perhaps still a draw because ab: and king goes to a5. But Skipper should have captured the bishop and try.

[d] 1k6/pBp5/P1P5/8/4K3/8/1b1r4/8 b - - 94 154

[hgm]

I don't think RxB helps. He recaptures with the a-Pawn. There is then still no way you can get the King out without allowing promotion, as the Bishop can only cover b8 from a7.

For positions like this paying attention to the 50-move rule could be helpful. At some point you must capture to avoid a 50-move draw, and RxB is the cheapest. Increasing passer bonuses won't do it, as white gets a protected 7th-rank passer by this. That should not be worth more than a minor, though. (As you can always dedicate a minor to stopping it.) So with Bishop + c7 it should still consider black better than c6+b7, and prever the sac over the draw. (But to no avail...)

[Henk]

O yes Bishop can't get to a7 for it blocks it's king and if king tries to escape you get b7-b8Q

[yurikvelo]

SF or Matefinder do not solve this.

Komodo 9.3 solve it fast at D=36, 65 MN

Code: Select all

-250,00	154. ... Rc2 155.Ke3 Bg7 156.Kd3 Rc3+ 157.Kd2 Rb3 158.Ke2 Bd4 159.Kf1 Rb2 160.Ke1 Rf2 161.Kd1 Bc3 162.Kc1 Rh2
-250,00	154. ... Rd6 155.Kf3 Bc1 156.Ke2 Bh6 157.Kf2 Re6 158.Kf3 Bg7 159.Kf4 Bd4 160.Kg4 Rf6 161.Kg3 Rf2 162.Kg4 Rf8
-250,00	154. ... Bf6 155.Kf5 Bg7 156.Ke4 Bh6 157.Kf3 Rd3+ 158.Kg4 Rd4+ 159.Kf3 Rc4 160.Kg2 Rc3 161.Kf2 Re3 162.Kg2 Rd3
-250,00	154. ... Bg7 155.Ke3 Rd5 156.Ke2 Re5+ 157.Kf2 Bh6 158.Kf3 Rd5 159.Kf2 Rd2+ 160.Kg3 Rd4 161.Kf3 Rc4 162.Kf2 Rc3
-250,00	154. ... Rd4+ 155.Ke3 Rd5 156.Ke4 Rd6 157.Kf3 Bc1 158.Ke2 Bh6 159.Kf2 Re6 160.Kf3 Bg7 161.Kf4 Bd4 162.Kf5 Rd6
-250,00	154. ... Rh2 155.Ke3 Rh3+ 156.Kd2 Bf6 157.Kc2 Rc3+ 158.Kd1 Re3 159.Kc2 Re2+ 160.Kc1 Rb2 161.Kd1 Bc3 162.Kc1 Bd4
-250,00	154. ... Bc3 155.Ke3 Rd4 156.Ke2 Rd6 157.Kf3 Bf6 158.Kg2 Bg7 159.Kf1 Rd8 160.Ke1 Rd3 161.Kf1 Rd1+ 162.Kf2 Rd2+
-250,00	154. ... Rf2 155.Ke3 Rf1 156.Ke2 Rf4 157.Kd3 Be5 158.Ke3 Rb4 159.Kd2 Rb2+ 160.Kd3 Bh8 161.Ke4 Rb3 162.Kf4 Bb2
-250,00	154. ... Bh8 155.Ke3 Rd4 156.Ke2 Be5 157.Ke3 Bf6 158.Kf3 Bg7 159.Kg3 Rd6 160.Kf4 Rd8 161.Kf5 Rd2 162.Ke4 Bh6
-250,00	154. ... Bc1 155.Ke3 Rd5+ 156.Kf3 Rd6 157.Ke2 Bh6 158.Kf2 Re6 159.Kf3 Bg7 160.Kf4 Bd4 161.Kf5 Re2 162.Kf4 Re8

[velmarin]

Victory is easy for black.
Not need to be an advanced player to see it.
[d]1k6/pBp5/P1P5/5K2/1r6/8/1b6/8 w - - 0 1

Analysis by Komodo 9.42 64-bit:

Code: Select all

1. -+  (-250.00): 156.Rg5 Txb7 157.cxb7 c5 158.Rf5 c4 159.Re4 Rc7 160.Re3 c3 161.Rd3 c2 162.Rxc2 Ae5 163.Rd3 Rb6 164.Re4 Ah2 165.Rd3 Rxa6 
2. -+  (-#19): 156.Rg6 Tb5 157.Rh6 Txb7 158.axb7 Ac1+ 159.Rg6 a5 160.Rg7 a4 161.Rf7 a3 162.Re7 Ab2 163.Re6 a2 164.Rf5 a1D 165.Rg4 De1 166.Rf3 De6 167.Rf4 De2 168.Rf5 Df3+ 169.Rg5 Aa3 170.Rg6 Ac1 
3. -+  (-#18): 156.Re6 Tb5 157.Rd7 Txb7 158.cxb7 c5 159.Re7 c4 160.Rd7 c3 161.Re6 c2 162.Rf5 c1D 163.Re4 Dc3 164.Rf4 Dd3 165.Rg4 De4+ 166.Rg5 Df3 167.Rg6 Df6+ 168.Rh5 Df5+ 169.Rh4 Df3 170.Rg5 De4 171.Rh5 
4. -+  (-#16): 156.Ac8 Rxc8 157.Re6 Tb6 158.Rd5 Txa6 159.Rc5 Tb6 160.Rc4 Txc6+ 161.Rd3 Rb8 162.Rd2 a5 163.Rd3 a4 164.Rd2 Tc3 165.Rd1 a3 166.Re2 a2 167.Rd1 a1D+ 168.Rd2 Dc1+ 169.Re2 Ta3 170.Rf2 Dc2+ 171.Rf1 
5. -+  (-#15): 156.Aa8 Rxa8 157.Re6 Tb6 158.Rd5 Txa6 159.Rc4 Txc6+ 160.Rd5 Tc3 161.Re4 Rb8 162.Rf4 a5 163.Rf5 a4 164.Re4 a3 165.Rd5 a2 166.Re4 a1D 167.Rf5 Df1+ 168.Re6 Te3+ 169.Rd7 Df5+ 170.Rc6 Tc3# 

[Sven]

Victory is easy for black.
Not need to be an advanced player to see it.
[d]1k6/pBp5/P1P5/5K2/1r6/8/1b6/8 w - - 0 1

Analysis by Komodo 9.42 64-bit:

Code: Select all

1. -+  (-250.00): 156.Rg5 Txb7 157.cxb7 c5 158.Rf5 c4 159.Re4 Rc7 160.Re3 c3 161.Rd3 c2 162.Rxc2 Ae5 163.Rd3 Rb6 164.Re4 Ah2 165.Rd3 Rxa6 
2. -+  (-#19): 156.Rg6 Tb5 157.Rh6 Txb7 158.axb7 Ac1+ 159.Rg6 a5 160.Rg7 a4 161.Rf7 a3 162.Re7 Ab2 163.Re6 a2 164.Rf5 a1D 165.Rg4 De1 166.Rf3 De6 167.Rf4 De2 168.Rf5 Df3+ 169.Rg5 Aa3 170.Rg6 Ac1 
3. -+  (-#18): 156.Re6 Tb5 157.Rd7 Txb7 158.cxb7 c5 159.Re7 c4 160.Rd7 c3 161.Re6 c2 162.Rf5 c1D 163.Re4 Dc3 164.Rf4 Dd3 165.Rg4 De4+ 166.Rg5 Df3 167.Rg6 Df6+ 168.Rh5 Df5+ 169.Rh4 Df3 170.Rg5 De4 171.Rh5 
4. -+  (-#16): 156.Ac8 Rxc8 157.Re6 Tb6 158.Rd5 Txa6 159.Rc5 Tb6 160.Rc4 Txc6+ 161.Rd3 Rb8 162.Rd2 a5 163.Rd3 a4 164.Rd2 Tc3 165.Rd1 a3 166.Re2 a2 167.Rd1 a1D+ 168.Rd2 Dc1+ 169.Re2 Ta3 170.Rf2 Dc2+ 171.Rf1 
5. -+  (-#15): 156.Aa8 Rxa8 157.Re6 Tb6 158.Rd5 Txa6 159.Rc4 Txc6+ 160.Rd5 Tc3 161.Re4 Rb8 162.Rf4 a5 163.Rf5 a4 164.Re4 a3 165.Rd5 a2 166.Re4 a1D 167.Rf5 Df1+ 168.Re6 Te3+ 169.Rd7 Df5+ 170.Rc6 Tc3# 

How can you enforce to reach the position in your diagram from the original position above?

I still think the original position is a draw.
EDIT: Now I see how it works ... nice!

[Nordlandia]

That position is similar to this study:

[d]7k/8/8/8/6p1/4QpPb/5PpP/6K1 w - - 0 1

The winning methods consists of pushing the black king to the a-rank then quickly capture the bishop so the g-pawn can outrun the king.

[Sven]

That position is similar to this study:

[d]7k/8/8/8/6p1/4QpPb/5PpP/6K1 w - - 0 1

The winning methods consists of pushing the black king to the a-rank then quickly capture the bishop so the g-pawn can outrun the king.

Do you mean a-file or 1st rank? I guess the latter, since a-file would not be sufficient ...

[Nordlandia]

First rank of course

[Henk]

Outside rectangle (b3,h3,h8, b8) but then queen should be able to capture Bh3 and that takes another move. So outside (a2, h2, h8, a8)