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  1. #1
    Monster of the deep Kevin Bonham's Avatar
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    Endgame Corner: Two Rooks vs Rook and Pawn

    I bailed out to this with Black in a casual game. About seventy moves later (yes, the pawn had to move a few times) my opponent blundered and I drew, but we determined that he had a clear win on the board in the final position.

    Is this won? I assume it is. What is the winning method?

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    Last edited by Kevin Bonham; 29-10-2004 at 06:47 PM.

  2. #2
    . eclectic's Avatar
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    Quote Originally Posted by Kevin Bonham
    I bailed out to this with Black in a casual game. About seventy moves later (yes, the pawn had to move a few times) my opponent blundered and I drew, but we determined that he had a clear win on the board in the final position.

    Is this won? I assume it is. What is the winning method?
    kevin,

    may i have clarification?

    is board correctly orientated?

    ie is black pawn on starting or penultimate rank?

    thanks

    eclectic
    .

  3. #3
    Illuminati Bill Gletsos's Avatar
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    Quote Originally Posted by eclectic
    kevin,

    may i have clarification?

    is board correctly orientated?

    ie is black pawn on starting or penultimate rank?

    thanks

    eclectic
    I believe Kevin has it setup correctly.
    I base this on his comments that after that position (approx 70 moves later) the game was drawn and that the pawn had moved several times. This would be impossible if it was already on the 7th rank.

  4. #4
    Monster of the deep Kevin Bonham's Avatar
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    Board is correctly oriented. Pawn had never moved. Oh, it's White to move.

  5. #5
    CC Grandmaster Garvinator's Avatar
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    Quote Originally Posted by Kevin Bonham
    Board is correctly oriented. Pawn had never moved. Oh, it's White to move.
    advancing the king to f3 would have to be good wouldnt it?

  6. #6
    Monster of the deep Kevin Bonham's Avatar
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    Quote Originally Posted by ggrayggray
    advancing the king to f3 would have to be good wouldnt it?
    Well, yes, he did that, and brought it all the way up to near where my pawn was, but notice how my pawn not having moved means my rook can check his king all over the place once his king gets too close.

  7. #7
    Illuminati Bill Gletsos's Avatar
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    1. Ra8+ Kg7 2. Ra3.
    Anything other than Kf8 is mate in 26.
    so 2..Kf8 3. Rc8+
    Black must play K3e7 as Kg7 leads to mate in 18 by fiest playing Eh3 which forces a rook swap.
    So 3..Ke7 4. Kd7 or Kd6 is forced as Kf6 allows Rc6+ and Kg7 or Kg5 again allows Rh3 forcing the rook swap.
    If 4..Kd6 then Rd8+ followed by Rd1 and its mate in 20.
    If 4..Kd7 then 5. Rc1 and its mate in 21 after Rg7+ or ir mate quickly or a rook is sawpped of if 5.. Rh4 or Rh5.

  8. #8
    CC Grandmaster Garvinator's Avatar
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    and of course you worked all this out without computer analysis right

  9. #9
    Illuminati Bill Gletsos's Avatar
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    Quote Originally Posted by ggrayggray
    and of course you worked all this out without computer analysis right
    I worked some of it out without computer analysis.
    e.g I realised if the K was on g7 you can find ways to swap the rook on the h file. Also that if the K wandered onto the e file you can generate mate threats with the two rook file shuffle or swap rooks.

    I used a computer to get me the mate in X numbers.

  10. #10
    CC International Master JGB's Avatar
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    A really good question.
    The computers are not so good here, you have to set Fritz on the right journey first. If I leave the base position as it is and give it to Fritz he just wanders around with a + 6 but does not know what to do with it. Only after bringing the king to his correct place will Fritz find the mate in X.

  11. #11
    Monster of the deep Kevin Bonham's Avatar
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    *bump*

    I don't think they had six-piece tablebases when I posted this thread.

    It's a win - quite easily - and here is another example line:

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    Last edited by Kevin Bonham; 16-03-2015 at 07:45 PM.

  12. #12
    CC International Master ElevatorEscapee's Avatar
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    Quote Originally Posted by Bill Gletsos View Post
    1. Ra8+ Kg7 2. Ra3.
    Anything other than Kf8 is mate in 26.
    so 2..Kf8 3. Rc8+
    Black must play K3e7 as Kg7 leads to mate in 18 by fiest playing Eh3 which forces a rook swap.
    So 3..Ke7 4. Kd7 or Kd6 is forced as Kf6 allows Rc6+ and Kg7 or Kg5 again allows Rh3 forcing the rook swap.
    If 4..Kd6 then Rd8+ followed by Rd1 and its mate in 20.
    If 4..Kd7 then 5. Rc1 and its mate in 21 after Rg7+ or ir mate quickly or a rook is sawpped of if 5.. Rh4 or Rh5.
    No wonder Bill found a pre-tablebase win, he was using an Equi-hopper!
    "On my chess set, all the pawns are Hamburglers" ~ Homer Simpson.

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