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Subject: Re: hard test position from my game

Author: Uri Blass

Date: 12:43:08 03/11/05

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On March 11, 2005 at 15:29:46, Uri Blass wrote:

>On March 11, 2005 at 14:29:54, John Merlino wrote:
>
>>On March 11, 2005 at 14:16:45, Terry McCracken wrote:
>>
>>>On March 11, 2005 at 13:33:45, John Merlino wrote:
>>>
>>>>On March 11, 2005 at 12:22:38, Uri Blass wrote:
>>>>
>>>>>[D]r2qk2r/pb1nbppp/1pp5/3BP3/8/2N3P1/PP2PP1P/R1BQ1RK1 w kq - 0 12
>>>>>
>>>>>The following position happened in my last tournament game.
>>>>>
>>>>>I chose a move in tal's style that is not typical to my style and played Bxf7+
>>>>>
>>>>>Note that I did not see that this move win a pawn when I played it and I later
>>>>>blundered in the game at move 17 and played a move that probably let my opponent
>>>>>to escape with a draw but my opponent also blundered so I was a pawn up from the
>>>>>sacrifice.
>>>>>
>>>>>Note that inspite of the fact that I won the game I think that it was a
>>>>>practical mistake to play 12.Bxf7+ [I am not tal and I should not try to play
>>>>>like him(espacially when my position is better) if I want to have better
>>>>>results] and 12.Be4 is a better practical move because it gives white a
>>>>>positional advantage with no risk.
>>>>>
>>>>>Uri
>>>>
>>>>CM9_R1 on an AMD 2500 says this:
>>>>
>>>>Time	Depth	Score	Positions	Moves
>>>>0:00	1/3	1.00	768		12.Bg2 Nxe5 13.Bf4
>>>>0:00	1/4	1.12	2320		12.Bg2 O-O 13.Bf4 Nc5 14.Be3
>>>>0:00	1/5	1.08	11537		12.Bg2 Nxe5 13.Bf4 Nc4 14.Qa4
>>>>0:00	1/6	0.92	29117		12.Bg2 Nxe5 13.Bf4 Ng6 14.Qa4 Nxf4
>>>>					15.Bxc6+ Bxc6 16.Qxc6+ Kf8 17.gxf4
>>>>0:00	1/6	0.93	39939		12.Bh1 O-O 13.f4 Bc5+ 14.e3 Bb4
>>>>					15.a3
>>>>0:02	1/7	0.80	135184		12.Bh1 Nxe5 13.Bf4 Ng6 14.Qa4 O-O
>>>>					15.Rfd1
>>>>0:02	1/7	0.92	168267		12.Bg2 Nxe5 13.Bf4 Ng6 14.Qa4 Nxf4
>>>>					15.Bxc6+ Bxc6 16.Qxc6+ Kf8 17.gxf4
>>>>0:03	1/8	0.72	252492		12.Bg2 Nxe5 13.Qa4 O-O 14.Bf4 Bd6
>>>>					15.Rad1 Qe7 16.Ne4
>>>>0:05	1/8	1.03	569553		12.Be4 Nxe5 13.Qc2 Bc5 14.Bf4 Qf6
>>>>					15.Rad1 g5
>>>>0:09	1/9	0.84	1323048		12.Be4 Nc5 13.Bg2 Qc7 14.f4 Rd8
>>>>					15.Qc2 O-O 16.Be3 Ba6
>>>>0:16	1/10	1.00	3199543		12.Be4 Nc5 13.Bg2 Qc7 14.f4 Rd8
>>>>					15.Qc2 O-O 16.Be3 Ba6 17.Rad1
>>>>0:41	1/11	0.85	8961628		12.Be4 Nxe5 13.Qc2 Ng6 14.h4 Bf6
>>>>					15.Rd1 Qe7 16.h5 Ne5 17.Bf4 Rd8
>>>>					18.Rxd8+ Qxd8 19.Bxh7
>>>>1:41	1/12	1.01	23739569	12.Be4 Nxe5 13.Qc2 Ng6 14.Be3 O-O
>>>>					15.Rad1 Qb8 16.f4 Rd8 17.Bg2 Qc8
>>>>					18.Ne4
>>>>
>>>>After forcing 12.Bxf7+ Kxf7 13.e6+ Kxe6+ 14.Qb3+ Kf6, it says this....
>>>>
>>>>Time	Depth	Score	Positions	Moves
>>>>0:00	1/4	-0.08	10900		15.Rd1 Qe8 16.Bf4 Kg6 17.Qc4
>>>>0:00	1/3	-0.86	2919		15.Rd1 g5 16.h4 Kg7 17.Bxg5 Bxg5
>>>>					18.hxg5 Qxg5
>>>>0:00	1/3	-1.01	3458		15.Be3 Nc5 16.Qc4 Kg6
>>>>0:00	1/3	-0.91	4594		15.Ne4+ Kg6 16.Nd6 Bxd6 17.Qd3+
>>>>					Kf7 18.Qxd6
>>>>0:00	1/4	-0.08	9708		15.Rd1 Qe8 16.Bf4 Kg6 17.Qc4
>>>>0:00	1/4	-0.91	13484		15.Ne4+ Kg6 16.Qe6+ Nf6 17.Be3 Qd7
>>>>0:00	1/4	-0.51	16961		15.Be3 Kg6 16.Qe6+ Nf6 17.Rad1 Qc7
>>>>0:00	1/3	-0.86	2919		15.Rd1 g5 16.h4 Kg7 17.Bxg5 Bxg5
>>>>					18.hxg5 Qxg5
>>>>0:00	1/4	-0.08	9708		15.Rd1 Qe8 16.Bf4 Kg6 17.Qc4
>>>>0:00	1/5	-0.17	24593		15.Rd1 Qe8 16.Qc4 Ne5 17.Qf4+ Ke6
>>>>					18.Be3
>>>>0:00	1/6	-0.11	74280		15.Rd1 Qe8 16.Be3 c5 17.Bf4 Kg6
>>>>					18.Nd5
>>>>0:01	1/7	-0.08	330626		15.Rd1 Qe8 16.Rd4 c5 17.Ne4+ Kg6
>>>>					18.Qe6+ Nf6 19.Nxc5
>>>>0:03	1/8	-0.18	831288		15.Rd1 Qe8 16.Ne4+ Kg6 17.Qe6+
>>>>					Nf6 18.Nxf6 gxf6 19.Bf4 Rd8 20.e4
>>>>					Rxd1+ 21.Rxd1
>>>>0:12	1/9	0.32	3211265		15.Rd1 Qe8 16.Ne4+ Kg6 17.Qe6+
>>>>					Nf6 18.Nxf6 gxf6 19.Rd7 Bc8 20.Qg4+
>>>>					Kf7 21.Qh5+ Ke6
>>>>0:34	1/10	0.52	9188889		15.Rd1 Qe8 16.Ne4+ Kg6 17.Rd4 h5
>>>>					18.Ng5 Bxg5 19.Qd3+ Kh6 20.Bxg5+
>>>>					Kxg5 21.Rxd7 Rd8
>>>>1:34	1/11	0.66	26541817	15.Rd1 Qe8 16.Ne4+ Kg6 17.Rd4 h5
>>>>					18.Ng5 Bxg5 19.Qd3+ Kh6 20.Bxg5+
>>>>					Kxg5 21.Rxd7 Bc8 22.Rxg7+ Kh6
>>>>
>>>>jm
>>>
>>>Check my lines...it appears Bxf7+!! will eventually win in style.
>>>
>>>I'm sure there is room for improvement.
>>>
>>>http://www.talkchess.com/forums/1/message.html?416358
>>
>>The King's final PV agrees with your first line all the way up to 22.Kh6 (where
>>the PV ends). Since this is 22-ply away from the initial position, and the eval
>>is going up with each depth, you are probably correct that Bxf7+ is also a
>>winner.
>>
>>Forcing some moves down this line, it seems that 21...Kh6 might be better than
>>21...Bc8, but the eval is +2 for White at this point, so it definitely looks
>>good.
>>
>>I think the hard part for a human OTB would be finding the Knight sac 18.Ng5,
>>but Uri would know better than I about this.
>>
>>jm
>
>Practically in the game I missed the fact that 17.Rd4 is a strong move and
>played after 30 minutes of thinking 17.Qe6+ that is good only for a draw against
>correct defence.
>
>fortunately my opponent also blundered and after 17...Nf6 18.Nxf6 Bxf6? 19.Qg4+
>I got position with a pawn advantage
>
>I did not see during the game more than a draw after 17...gxf6
>
>Uri

I can add that I also did not find in the analysis after the game more than a
draw after 17...gxf6 and I guess that my opponent could draw the game.

I agree that Objectively Bxf7+ is good but for me it was a practical mistake for
the simple reason that I could not find the right line later inspite of
evaluating that there must be a win after it based on positional evaluation of
the position after 16.Rd1 that I predicted when I played 12.Bxf7+.

I thought at that time that after Qe8 I have the idea of 17.Qd3 with double
threat against the knight and Nd6+ without seeing that black can reply 17...Ne5
at that time.

I was not sure also that I have a win after moves like 15...Kf5 but I decided
not to spend energy about analyzing moves like that move because of positional
evaluation that I probably have a win.


Note that I say that Bxf7+ was a practical mistake(and of course objectively a
good move) also because the opponent is more than 200 elo weaker than me(My
rating is 2051 when the rating of the opponent is only 1805) and espacially
against that type of opponent it is a practical mistake to sacrifice when you do
not see everything because I probably have good chances to win against him in
quiet game and a wrong sacrifice has good chances to destroy the win.

Uri



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