Author: Sune Larsson
Date: 10:08:22 06/26/01
Go up one level in this thread
On June 26, 2001 at 12:52:52, martin fierz wrote:
>On June 26, 2001 at 12:18:53, Dann Corbit wrote:
>
>>On June 26, 2001 at 12:09:25, martin fierz wrote:
>>
>>>hi dann,
>>>
>>>>you know, the one where I claimed there was a blunder? Turns out that there is
>>>>a perpetual check if you take the rook from this position. The only problem is,
>>>>I can't find it! Help me find what is obvious to a good player but is way over
>>>>my head.
>>>>
>>>>[D]4k2r/rp5p/pR4p1/R3qp2/3pp1PQ/8/2P4P/6K1 b k -
>>>>Qxa5 {forced, I think}
>>>>Rxg6 {forced, I think}
>>>
>>>not very forced, i think :-)
>>>Qf6 looks like the perpetual which is obvious to strong players, but not to
>>>computers. you can go and take the pawns on c2 and g4 with check still, but
>>>that will still make it a perpetual, i think... (no computer here...)
>>
>>I'm afraid you really don't see how dense I can be. Someone is going to have to
>>spell it out for me. I mean *literally* do this and do that and to this and do
>>that and see: the perpetual check!
>>
>>Here is what I see:
>>[D]4k2r/rp5p/pR3Qp1/q4p2/3pp1P1/8/2P4P/6K1 b k -
>>
>>In the worst case, Qxb6 Qxb6 and it's two rooks and a big pawn advantage verses
>>a queen.
>ok, lets see your qxb6 line,
>
>1... qxa5 2.qf6 qxb6 3. qxb6 ra8 (this one really looks forced) then i go 4.
>qe6+. moving to the right will take you nowhere:
>4....kf8 5. qf6+ kg8 6. qe6+ kg7 7. qe7+ kh6 8. qh4+ and we're back where we
>started, so you must go 4... kd8 5. qd6+ kc8 and now black lacks all
>coordination. so white has time for 6. gxf5 and fritz gives lots of 0.00
>evaluations here - perpetuals everywhere. the point of gf5 is to open up the
>position a bit for the perpetual - i wanted to go 6. qe6+ first but black can
>run with his king to g5 and white has no check anymore. now anyway 6. ..gf5 will
>take you to an immediate draw with qc5+ and checks along the 5th row with the
>queen as you can play qxf5+ now which you couldnt before.
>
>so the qxb6 is obviously not good enough for more than a draw.
>
>a better try is
>
>
>
>1...Qxa5 2.Qf6 Qe1+ 3.Kg2 Qe2+ 4.Kg1 Qxg4+ 5.Kh1 Qd1+ 6.Kg2 Qxc2+ 7.Kg1 and
>now you can go looking for some way to escape the draw. i admit that this is
>looking good for black after 7...Kd7 :-(
And then 8.Qxd4+ Kc7 9.Qd6+ Kc8 10.Qe6+ Kb8 11.Qe5+ Qc7 12.Qxh8+ Qc8
13.Qe5+ Ka8 14.Re6 and black must take out the perpetuals.
Sune
>
>
>cheers
> martin
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