EVENT
BOARDSIZE 19
SETUP W C16 E16 H17 C12 R14 Q14 R11 R17 
SETUP B K17 C10 O16 Q16 R15 S16 
MARK 2@S16 1@R17
COM
Problem 137. White to play.  

This time Black responds with the diagonal move of 2. What should
White do in this case ? 
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W 1 P18
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

In this case, the knight move of White 1 is the only way. This
move was criticised in Problem 125, but in this case it is good.
<=
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  VAR
  W 1 P17
  COM
  Failure.

  If White plays 1 ...
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  B 2 P16
  W 3 O18
  COM
  ... and 3, ...
  ENDCOM
  B 4 Q17
  W 5 Q18
  B 6 O17
  W 7 P18
  B 8 S18
  COM
  ... the sequence continues up to 8.
  ENDCOM
  W 9 R18
  COM
  If White connects at 9, ...
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    VAR
    W 9 M17
    COM
    If White 9 here, ...
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    B 10 R18
    COM
    ... Black takes the corner with 10. Either way, Black ends up
    with a thick position.
    <=
    ENDCOM
    ENDVAR
  B 10 S14
  COM
  ... Black plays 10.
  <=
  ENDCOM
  ENDVAR