A Position That Stumps Computers

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Terry McCracken
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A Position That Stumps Computers

Post by Terry McCracken »

First posted in CCC last spring.

[fen]4q1kr/p6p/1prQPppB/4n3/4P3/2P5/PP2B2P/R5K1 w - - 0 1 [/fen]

Gusev-Auerbach 1946 Qxe5!!
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Harvey Williamson
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Post by Harvey Williamson »

Hi Terry,

I tried a few engines and none solve this one.

Here is Hiarcs analysis:

New game, Blitz:15'+5"
4q1kr/p6p/1prQPppB/4n3/4P3/2P5/PP2B2P/R5K1 w - - 0 1

Analysis by HIARCS 11.78 MP:

1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bd2 Qe7 4.Qxe7 Rxe7 5.Be3 Rxe4 6.Kf2 Re6 7.Bc4 Rc6 8.Bd5 Rd6
-/+ (-0.81) Depth: 12/27 00:00:00 821kN
1.Qd5
-/+ (-0.80) Depth: 12/29 00:00:00 1009kN
1.Qd5
=/+ (-0.56) Depth: 12/29 00:00:00 1100kN
1.Qd5 Rxe6 2.Bd1 Qc6 3.Bb3 Qxd5 4.Bxd5 Kf7 5.Rf1 Rhe8 6.Bxe6+ Rxe6
=/+ (-0.34) Depth: 12/29 00:00:00 1298kN
1.Qd5 Rxe6 2.Bd1 Qd7 3.Qxd7 Nxd7 4.Bb3 Kf7 5.Be3 Rhe8 6.Rd1 Nc5 7.Bxc5 bxc5 8.Rd7+ R8e7 9.Bxe6+ Kxe6 10.Rd5 f5 11.Rxc5 fxe4
=/+ (-0.30) Depth: 13/29 00:00:01 1949kN
1.Qd5 Rxe6 2.Bd1 Qd7 3.Qxd7 Nxd7 4.Bb3 Kf7 5.Be3 Ne5 6.Rf1 Rc8 7.Bxe6+ Kxe6 8.Kg2 Rd8 9.Bh6 b5 10.Bg7 Rd2+
=/+ (-0.37) Depth: 14/31 00:00:02 3022kN
1.Qa3
=/+ (-0.36) Depth: 14/39 00:00:02 3820kN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Bxf7+ Qxf7 5.Qb8+ Re8 6.Qxb6 Qe6 7.Qc7 Qe7 8.Qc4+ Qf7 9.Qc6 Re6 10.Qa8+ Re8 11.Qc6
= (-0.07) Depth: 14/39 00:00:03 5127kN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Bxf7+ Qxf7 5.Qb8+ Re8 6.Qxb6 Qe6 7.Qc7 Qe7 8.Qc4+ Qe6 9.Qc7
= (0.00) Depth: 15/39 00:00:04 7033kN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Bxf7+ Qxf7 5.Qb8+ Re8 6.Qxb6 Qe6 7.Qc7 Qe7 8.Qc4+ Qe6 9.Qc7
= (0.00) Depth: 16/41 00:00:07 10779kN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Bxf7+ Qxf7 5.Qb8+ Re8 6.Qxb6 Qe6 7.Qc7 Qe7 8.Qc4+ Qe6 9.Qc7
= (0.00) Depth: 17/42 00:00:13 20952kN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Qc7 b5 5.Bb3 Re1+ 6.Rxe1 Qxe1+ 7.Kg2 Qe2+ 8.Kg1 Qe1+
= (0.00) Depth: 18/51 00:00:31 50676kN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Qc7 b5 5.Bb3 Re1+ 6.Rxe1 Qxe1+ 7.Kg2 Qe2+ 8.Kg1 Qe1+
= (0.00) Depth: 19/51 00:00:51 84678kN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Qc7 b5 5.Bb3 Re1+ 6.Rxe1 Qxe1+ 7.Kg2 Qe2+ 8.Kg1 Qe1+
= (0.00) Depth: 20/52 00:02:18 223mN
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Qc7 b5 5.Bb3 Re1+ 6.Rxe1 Qxe1+ 7.Kg2 Qe2+ 8.Kg1 Qe1+
= (0.00) Depth: 21/53 00:03:51 373mN, tb=2
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Qc7 b5 5.Bb3 Re1+ 6.Rxe1 Qxe1+ 7.Kg2 Qe2+ 8.Kg1 Qe1+
= (0.00) Depth: 22/56 00:08:12 793mN, tb=4
1.Qa3 Rxe6 2.Qxa7 Nf7 3.Bc4 Rxe4 4.Qc7 b5 5.Bb3 Re1+ 6.Rxe1 Qxe1+ 7.Kg2 Qe2+ 8.Kg1 Qe1+
= (0.00) Depth: 23/61 00:22:20 2186mN, tb=5799

(Williamson, 16.09.2007)
Dostojewsky
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Post by Dostojewsky »

Absolutly amazing. :P :P :P

Please send us the complete game. Rybka on a quadcore can´t see the win after 1.Qxe5 dxe5.

It evaluates 2.Rf1 with -0,42.

Regards
TL
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Terry McCracken
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Post by Terry McCracken »

Dostojewsky wrote:Absolutly amazing. :P :P :P

Please send us the complete game. Rybka on a quadcore can´t see the win after 1.Qxe5 dxe5.

It evaluates 2.Rf1 with -0,42.

Regards
TL
I'm afraid I don't have the complete game, I wish I did, just the critical position.

Computers just don't "understand" this position. I doubt the infamous Hydra or Deep Blue, (if still around), could solve it.

Although 2. Rf1! is the next move. It puts Black in Zugzwang. The Black Queen will be tied up defending the back rank and White will win with pawn advances on the Q-Side.

Terry
Dostojewsky
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Post by Dostojewsky »

That´s a pitty.

The Quadcore-Rybka can´t see the win after 1 hour in the 1.Qxe5 fxe5 line.

Neue Partie
4q1kr/p6p/1pr1P1pB/4p3/4P3/2P5/PP2B2P/R5K1 w - - 0 1

Analysis by Rybka 2.3.2a mp :

2.Td1 De7 3.Tf1 Tc8 4.Ld1 a5 5.Tf7 Dxf7 6.exf7+ Kxf7 7.Lb3+ Kf6 8.h4 Tc5
-+ (-4.01) Tiefe: 14 00:00:00
2.Td1 De7 3.Tf1 Tc8 4.Ld1 a5 5.Tf7 Dxf7 6.exf7+ Kxf7 7.Lb3+ Kf6 8.h4 Tc5
-+ (-4.01) Tiefe: 15 00:00:00
2.Td1 Dxe6 3.Td8+ Kf7 4.Txh8 Dxa2 5.Txh7+ Kg8 6.Tg7+ Kh8 7.Td7 Dxb2 8.Ld2 a5
-+ (-4.40) Tiefe: 16 00:00:01 1182kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Tf7 Dxf7 8.exf7+ Kxf7
-+ (-2.70) Tiefe: 16 00:00:03 2473kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Tf7 Dxf7 8.exf7+ Kxf7
-+ (-2.70) Tiefe: 17 00:00:03 2570kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Tf7 Dxf7 8.exf7+ Kxf7
-+ (-2.70) Tiefe: 18 00:00:04 2729kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.Tf7 Dxf7
-+ (-2.64) Tiefe: 19 00:00:05 3172kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.Tf7 Dxf7
-+ (-2.50) Tiefe: 20 00:00:06 3959kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.Kg3 De8
-+ (-1.86) Tiefe: 21 00:00:14 8401kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.Kg3 De8
-+ (-1.66) Tiefe: 22 00:00:20 11900kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.a4 De8
-+ (-1.52) Tiefe: 23 00:00:30 16792kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.a4 De8
µ (-1.02) Tiefe: 24 00:00:50 27501kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.a4 De8
µ (-0.74) Tiefe: 25 00:01:36 51304kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.a4 De8
³ (-0.50) Tiefe: 26 00:02:49 91868kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.a4 De8
³ (-0.52) Tiefe: 27 00:04:03 136429kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.a4 De8
³ (-0.42) Tiefe: 28 00:07:08 240480kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Tc4 6.Lb3 b5 7.Kg2 a6 8.a4 De8
³ (-0.42) Tiefe: 29 00:10:26 354882kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 b5 6.Lb3 Tc8 7.Tf7 Te8 8.Txe7 Txe7
= (0.00) Tiefe: 30 00:26:23 852148kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Dc5+ 6.Kh1 Tg7 7.Lb3 De7 8.a4 a6
= (0.00) Tiefe: 31 00:32:51 1052221kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Dc5+ 6.Kh1 Tg7 7.Lb3 De7 8.a4 a6
= (0.00) Tiefe: 32 00:46:53 1484930kN
2.Tf1 Tc7 3.Lb5 Dd8 4.Ld7 De7 5.La4 Dc5+ 6.Kh1 Tg7 7.Lb3 De7 8.a4 a6
= (0.00) Tiefe: 33 01:23:51 2644416kN

(, W 16.09.2007)
BigBen

Post by BigBen »

Hi,


Gusev,Y - Averbakh,Y [B70]
Moscow, 1951

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be2 Nc6 7.Nb3 Bg7 8.0-0 Be6 9.f4 Rc8 10.f5 Bd7 11.g4 Ne5 12.g5 Ng8 13.Nd5 f6 14.Be3 b6 15.Nd4 Kf7 16.c3 Qe8 17.Ne6 Bxe6 18.fxe6+ Kf8 19.Nxf6 Nxf6 20.gxf6 Bxf6 21.Bh6+ Kg8 22.Rxf6 exf6 23.Qxd6 Rc6 24.Qxe5 fxe5 25.Rf1 Rc8 26.Bd1 Rc4 27.Bb3 b5 28.Bxc4 bxc4 29.b3 a5 30.bxc4 Qe7 31.Kg2 Qa3 32.Rf2 Qe7 33.Rf1 g5 34.Rf5 g4 35.c5 Qd8 36.c6 Qe7 37.c7 1-0

Regards
Tony
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Post by Dostojewsky »

Thx a lot.

Now i am remembering this magic game. I hope i have next week time to have a clother look on it.

TL
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Terry McCracken
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Post by Terry McCracken »

BigBen wrote:Hi,


Gusev,Y - Averbakh,Y [B70]
Moscow, 1951

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be2 Nc6 7.Nb3 Bg7 8.0-0 Be6 9.f4 Rc8 10.f5 Bd7 11.g4 Ne5 12.g5 Ng8 13.Nd5 f6 14.Be3 b6 15.Nd4 Kf7 16.c3 Qe8 17.Ne6 Bxe6 18.fxe6+ Kf8 19.Nxf6 Nxf6 20.gxf6 Bxf6 21.Bh6+ Kg8 22.Rxf6 exf6 23.Qxd6 Rc6 24.Qxe5 fxe5 25.Rf1 Rc8 26.Bd1 Rc4 27.Bb3 b5 28.Bxc4 bxc4 29.b3 a5 30.bxc4 Qe7 31.Kg2 Qa3 32.Rf2 Qe7 33.Rf1 g5 34.Rf5 g4 35.c5 Qd8 36.c6 Qe7 37.c7 1-0

Regards
Tony
Thanks Tony!

Where on Earth did You Find It?!..Regards,
Terry
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Terry McCracken
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Re: A Position That Stumps Computers

Post by Terry McCracken »

Terry McCracken wrote:First posted in CCC last spring.

[fen]4q1kr/p6p/1prQPppB/4n3/4P3/2P5/PP2B2P/R5K1 w - - 0 1 [/fen]

Gusev-Auerbach 1946 Qxe5!!
The game is now recorded at chessgames.com.

http://www.chessgames.com/perl/chessgame?gid=1472988

Recording Regards,
Terry
BigBen

Post by BigBen »

Hi,
It is in my database. I checked the source and it comes from a database called Horrorbase from years back, which after cleaning and sorting etc was imported into my main database.

Regards
Tony
Terry McCracken wrote:
BigBen wrote:Hi,


Gusev,Y - Averbakh,Y [B70]
Moscow, 1951

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be2 Nc6 7.Nb3 Bg7 8.0-0 Be6 9.f4 Rc8 10.f5 Bd7 11.g4 Ne5 12.g5 Ng8 13.Nd5 f6 14.Be3 b6 15.Nd4 Kf7 16.c3 Qe8 17.Ne6 Bxe6 18.fxe6+ Kf8 19.Nxf6 Nxf6 20.gxf6 Bxf6 21.Bh6+ Kg8 22.Rxf6 exf6 23.Qxd6 Rc6 24.Qxe5 fxe5 25.Rf1 Rc8 26.Bd1 Rc4 27.Bb3 b5 28.Bxc4 bxc4 29.b3 a5 30.bxc4 Qe7 31.Kg2 Qa3 32.Rf2 Qe7 33.Rf1 g5 34.Rf5 g4 35.c5 Qd8 36.c6 Qe7 37.c7 1-0

Regards
Tony
Thanks Tony!

Where on Earth did You Find It?!..Regards,
Terry
IanO
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Re: A Position That Stumps Computers

Post by IanO »

Terry McCracken wrote:First posted in CCC last spring.

[fen]4q1kr/p6p/1prQPppB/4n3/4P3/2P5/PP2B2P/R5K1 w - - 0 1 [/fen]

Gusev-Auerbach 1946 Qxe5!!
Resurrecting this thread to check computer progress over the last seven years. In my opinion, the queen sac still leads to only a draw. The critical position came later:

[fen]4q1kr/p6p/4P1pB/4p3/2p1P3/1PP5/P6P/5RK1 b - - 0 6[/fen]

Here 29. … a5? was the game losing blunder, simply 29. … cxb3 30. axb3 a5 holds the draw. Any attempt by white to advance the pawns, king, or rook is met by perpetual check from the carefully positioned black queen. Can anybody prove me wrong?
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Post by rlsuth »

I'm still trying to find the win after 25.Rf1 Rc7 intending Re7 and I don't see how white makes progress.
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Post by Peter Grayson »

rlsuth wrote:I'm still trying to find the win after 25.Rf1 Rc7 intending Re7 and I don't see how white makes progress.
It is important to remember the Black King is under threat of mate that ties down Black to the defence of the back rank

After 25.Rf1 Rc7? 26.Bd1 Re7 27.Bb3 is #13.

It seems that White's killer move is indeed 25.Rf1 when at present Black has no defence to it. I'll look at few more potential Black defences but it does look to be a forced win for White.

Feel free to refute 27.Bb3 #13 and I'll get back to you.

PeterG
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Post by Peter Grayson »

BigBen wrote:Hi,
It is in my database. I checked the source and it comes from a database called Horrorbase from years back, which after cleaning and sorting etc was imported into my main database.

Regards
Tony
Terry McCracken wrote:
BigBen wrote:Hi,


Gusev,Y - Averbakh,Y [B70]
Moscow, 1951

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be2 Nc6 7.Nb3 Bg7 8.0-0 Be6 9.f4 Rc8 10.f5 Bd7 11.g4 Ne5 12.g5 Ng8 13.Nd5 f6 14.Be3 b6 15.Nd4 Kf7 16.c3 Qe8 17.Ne6 Bxe6 18.fxe6+ Kf8 19.Nxf6 Nxf6 20.gxf6 Bxf6 21.Bh6+ Kg8 22.Rxf6 exf6 23.Qxd6 Rc6 24.Qxe5 fxe5 25.Rf1 Rc8 26.Bd1 Rc4 27.Bb3 b5 28.Bxc4 bxc4 29.b3 a5 30.bxc4 Qe7 31.Kg2 Qa3 32.Rf2 Qe7 33.Rf1 g5 34.Rf5 g4 35.c5 Qd8 36.c6 Qe7 37.c7 1-0

Regards
Tony
Thanks Tony!

Where on Earth did You Find It?!..Regards,
Terry
Worth including in the game notes that White missed 23.Qd5 that looks to be winning too!

PeterG
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Re: A Position That Stumps Computers

Post by Peter Grayson »

IanO wrote:
Terry McCracken wrote:First posted in CCC last spring.

[fen]4q1kr/p6p/1prQPppB/4n3/4P3/2P5/PP2B2P/R5K1 w - - 0 1 [/fen]

Gusev-Auerbach 1946 Qxe5!!
Resurrecting this thread to check computer progress over the last seven years. In my opinion, the queen sac still leads to only a draw. The critical position came later:

[fen]4q1kr/p6p/4P1pB/4p3/2p1P3/1PP5/P6P/5RK1 b - - 0 6[/fen]

Here 29. … a5? was the game losing blunder, simply 29. … cxb3 30. axb3 a5 holds the draw. Any attempt by white to advance the pawns, king, or rook is met by perpetual check from the carefully positioned black queen. Can anybody prove me wrong?
It looks to be a forced win after 25.Rf1
Chess engines are not too good with Zugszwang positions and that is the theme of the game ...

[Event "Moscow, 1951"]
[Site "?"]
[Date "2014.06.03"]
[Round "?"]
[White "Gusev"]
[Black "Averbakh"]
[Result "1-0"]
[ECO "B70"]
[Annotator "Grayson,Peter"]
[PlyCount "57"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be2 Nc6 7. Nb3 Bg7 8.
O-O Be6 9. f4 Rc8 10. f5 Bd7 11. g4 Ne5 12. g5 Ng8 13. Nd5 f6 14. Be3 b6 15.
Nd4 Kf7 16. c3 Qe8 17. Ne6 Bxe6 18. fxe6+ Kf8 19. Nxf6 Nxf6 20. gxf6 Bxf6 21.
Bh6+ Kg8 22. Rxf6 exf6 23. Qxd6 (23. Qd5 $18) 23... Rc6 24. Qxe5 fxe5 25. Rf1
Rc8 (25... Rc7 $2 26. Bd1 b5 (26... Re7 $2 27. Bb3 {#13}) (26... Rg7 27. Bb3 {
#13} Re7 28. Bd5 {#12} a6 29. Kg2 {#11} a5 30. a4 {#10} Qd8 31. Rf7 Qe8 32.
Rxe7 {#7} Qxe7 33. Kh3 {#6} b5 34. axb5 {#5} a4 35. b6 a3 36. b7 Qh4+ 37. Kxh4
g5+ 38. Kxg5 a2 39. b8=Q#) 27. Bb3 Rc4 (27... Re7 28. Bd5 {#12} a5 29. Kg2 {#10
} a4 30. a3 {#9} Qd8 31. Rf7 {#7} Qe8 32. Rxe7 Qxe7) 28. a4 a6 {Houdini 4 Pro
x64:} 29. Ba2 Qe7 (29... Qd8 30. b4 {#21}) 30. b4 Qg7 31. Bxg7 Kxg7 32. Bxc4
bxc4 33. Rf7+ Kh6 34. e7 Re8 35. a5 Kh5 36. Rxh7+ Kg4 37. Rf7 g5 38. Kg2 Kh5
39. Rf6 Rxe7 40. Rxa6 Rf7 41. Re6 Kg4 42. Rxe5 Rd7 43. Rd5 Ra7 44. Rf5 Ra6 45.
h3+ Kh4 46. Kf3 Rd6 47. Rd5 Ra6 48. Ke3 Kg3 49. Rxg5+ Kh4 50. Rg4+ Kxh3 51. Rg5
Rd6 52. Rd5 Ra6 53. Kd4 Kg4 54. e5 Kf5 55. Rd6 Ra7 56. a6 Rg7 57. Rf6+ Kg5 58.
b5 Ra7 59. Kxc4 Ra8 60. Kd4 Rd8+ 61. Kc5 Re8 62. a7) 26. Bd1 Rc4 27. Bb3 b5 28.
a4 (28. Bxc4 {?} bxc4 29. b3 cxb3 (29... a5 {?? loses immediately} 30. bxc4 Qe7
$18 31. Kg2 Qa3 32. Rf2 Qe7 33. Rf1 g5 34. Rf5 g4 35. c5 Qd8 36. c6 Qe7 37. c7)
30. axb3 $11) 28... a6 {transposes into the earlier 25..Rc7 line} 29. Ba2 {+-}
1-0


PeterG
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