Test Position: Krogius-Niemala (Bad Lovisa) 1934

[Cubeman]

Hi Paulo,

Yes I thought the position was interesting because usually engines initially think that cxd3 wins for black, then switch to Qe8 thinking it is also much better for black, then see the danger in the line beginning with Qe8 Kf2! and finally switch to the correct Bxg5! So there are two temping moves to avoid.

Have a good day,

Some programs analyses d4, that loses.

Paulo Soares

Just not sure that d4 loses, as White can force a perpetual after Qg4 Kxh7 Qh5+ Kg8 Bxg6 fxg6 Qxg6+ etc.There is no time for the Kf2 manoever or Ke2.I think alot of engines like Black in the Bxg5 variation but to me it is unclear as Black is the exchange ahead but 2 pawns down.
Please give a winning line for White after d4?!

In the line with d4, white can castle long instead of playing Kf2 or Ke2 as SlowChess suggests:

SlowChess Blitz WV2.1 (190 MB hash) PIV 3.2 Prescott
FEN: r2q1rk1/pb2bp1R/1p4p1/4P1P1/2pp1P2/3BP3/PP1N2P1/R2QK3 w Q -

[15] 2.60 18:15.6 Qg4 Kxh7 Qh5+ Kg8 Bxg6 fxg6 Qxg6+ Kh8 O-O-O Bxg5 Rh1+ Bh4 Qh6+ Kg8 Rxh4 Qxh4 Qxh4 dxe3 Qg3+ Kf7 Qxe3 Bxg2 Qe2 Bd5 Nxc4
[14] 2.60 08:37.7 Qg4 Kxh7 Qh5+ Kg8 Bxg6 fxg6 Qxg6+ Kh8 O-O-O Bxg5 Rh1+ Bh4 Qh5+ Kg7 Rxh4 Qxh4 Qxh4 dxe3 Qg3+ Kf7 Qxe3 Rad8 f5
[13] 2.52 03:59.1 Qg4 Kxh7 Qh5+ Kg8 Bxg6 fxg6 Qxg6+ Kh8 O-O-O Bxg5 Rh1+ Bh4 Qh5+ Kg7 Rxh4 Qxh4 Qxh4 c3 Qg4+ Kh8 Qh5+ Kg7 Qg5+ Kf7 Qf6+ Kg8 Qg6+ Kh8 Qh6+ Kg8 Nc4
[12] 1.56 01:05.1 Qg4 Kxh7 Qh5+ Kg8 Bxg6 fxg6 Qxg6+ Kh8 O-O-O Bxg5 Rh1+ Bh4 Qh5+ Kg7 Rxh4 Rg8 e6 Qf6 Qh7+ Kf8 Qxb7
[11] 1.20 00:30.2 Qg4 Kxh7 Qh5+ Kg7 Qh6+ Kg8 Bxg6 fxg6 Qxg6+ Kh8 O-O-O Bxg5 Rh1+ Bh4 Qh5+ Kg7 Rxh4 Rg8 Qh7+ Kf8 Qxb7 Rg7
[10] 0.41 00:12.1 Qg4 Kxh7 Qh5+ Kg7 Qh6+ Kg8 Bxg6 fxg6 Qxg6+ Kh8 O-O-O Bxg5 Rh1+ Bh4 Qh6+ Kg8 Qg6+ Kh8 <draw>
[9] 0.41 00:08.8 Qg4 Kxh7 Qh5+ Kg7 Qh6+ <tt>
[8] -0.76 00:03.0 Qg4 dxe3 Qh4 exd2+ Kd1 Bf6 gxf6 Bf3+ gxf3 Qxd3
[8] -0.80 00:02.7 Qg4 {++}
[8] -0.80 00:01.7 Nxc4 b5 Rh6 bxc4 Bxc4 Qb6 Qxd4 Bxg2
[7] -1.52 00:00.5 Nxc4 b5 Nd6 Bxd6 Bxg6 Bb4+ Ke2 dxe3 Kxe3 Bxg2
[6] -1.52 00:00.3 Nxc4 b5 Nd6 Bxd6 Bxg6 Bb4+ Kf2 dxe3+ Kxe3 Bxg2
[6] -2.84 00:00.1 Nxc4 {++}
[6] -2.84 00:00.0 Bxg6 fxg6 Rh4 c3 bxc3 dxc3
[5] -2.68 00:00.0 Bxg6 fxg6 Rh4 Qd5 Qe2
[4] -2.08 00:00.0 Bxg6 fxg6 Rh6 Kg7 Nxc4 dxe3
[3] -2.40 00:00.0 Bxg6 fxg6 Rh6
[2] -1.76 00:00.0 Bxg6 fxg6

Also, It looks like white is still (much?) better in the line with Bxg5 but this is clearly Black's best chance. I had Glaurung-2-minus-epsilon-over-two analyze overnight the position after Bxg5 Bxg6 fxg6 Rxb7, and it evaluates it as +1.03 for white at depth=22. Unfortunately I closed the GUI before I could copy the analysis, but Glaurung was intending to play Bh4+ at this point.

I now see how d4 loses.Just as before I was using my Pocket PC to study the original position but did not specify castling rules when I set it up so it assumed that it was not possible.Good thing to remember next time I set up positions.

[PauloSoare]

This line it´s a winning line for whites. I have analysed more deeply
with computer help, and I didn´t saw any drawn for blacks.


[Event "120'/40+60'/20+30'"]
[Site "Residencia"]
[Date "2007.05.24"]
[Round "?"]
[White "New game"]
[Black "?"]
[Result "*"]
[Annotator "Soares,Paulo"]
[SetUp "1"]
[FEN "r2q1rk1/pb2bp1R/1p4p1/3pP1P1/2p2P2/3BP3/PP1N2P1/R2QK3 b Q - 0 1"]
[PlyCount "18"]
[EventDate "2007.??.??"]
[TimeControl "40/7200:20/3600:1800"]

1... d4 2. Qg4 Kxh7 3. Qh5+ Kg8 4. Bxg6 fxg6 5. Qxg6+ Kh8 6. O-O-O Bxg5 7. Rh1+
Bh4 8. Qh5+ Kg8 9. Rxh4 Qxh4 10. Qxh4 *



Rybka 2.2n2 mp analyses on an Athlon 2cores 3800+ after 10. Qxh4:

[d]r4rk1/pb6/1p6/4P3/2pp1P1Q/4P3/PP1N2P1/2K5 b - - 0 1

Analysis by Rybka 2.2n2 mp :

10...d4xe3
+- (1.89) Depth: 2 00:00:00
10...d4xe3
+- (2.09) Depth: 3 00:00:00
10...d4xe3
+- (2.11) Depth: 4 00:00:00
10...d4xe3 11.Qh4-g3+
+- (2.03) Depth: 5 00:00:00
10...d4xe3 11.Qh4-g3+
+- (2.15) Depth: 6 00:00:00 11kN
10...d4xe3 11.Qh4-g3+
+- (2.15) Depth: 7 00:00:00 30kN
10...d4xe3 11.Qh4-g4+
+- (2.33) Depth: 8 00:00:00 100kN
10...d4xe3 11.Qh4-g4+
+- (2.36) Depth: 9 00:00:01 181kN
10...d4xe3 11.Qh4-g4+
+- (2.56) Depth: 10 00:00:02 422kN
10...d4xe3 11.Qh4-g4+
+- (2.56) Depth: 11 00:00:02 592kN
10...d4xe3 11.Qh4-g4+
+- (2.67) Depth: 12 00:00:05 1108kN
10...d4xe3 11.Qh4-g4+
+- (2.60) Depth: 13 00:00:08 1998kN
10...d4xe3 11.Qh4-g4+
+- (2.61) Depth: 14 00:00:11 2507kN
10...d4xe3 11.Qh4-g4+
+- (3.33) Depth: 15 00:00:42 10270kN
10...d4xe3 11.Qh4-g4+
+- (3.44) Depth: 16 00:02:00 29212kN
10...Rf8-f7 11.e3xd4 Ra8-f8 12.Qh4-g4+ Rf7-g7 13.Qg4-e6+
+- (3.41) Depth: 16 00:03:30 52014kN
10...Rf8-f7 11.e3xd4 c4-c3 12.b2xc3 Rf7-g7 13.g2-g4 Ra8-c8 14.e5-e6 b6-b5 15.f4-f5 Rg7-h7 16.Qh4-f6 Rc8-f8 17.Qf6-e5
+- (3.47) Depth: 17 00:05:22 79262kN
10...Rf8-f7 11.e3xd4 c4-c3 12.b2xc3 Bb7-d5 13.f4-f5 Rf7-h7 14.Qh4-f6 Ra8-f8 15.Qf6-d6 Bd5-b7 16.Qd6-e6+ Rh7-f7 17.g2-g4
+- (3.47) Depth: 18 00:07:21 108mN
10...Rf8-f7 11.e3xd4 c4-c3 12.b2xc3 Bb7-d5 13.f4-f5 Rf7-h7 14.Qh4-f6 Ra8-f8 15.Qf6-d6 Bd5-a8 16.g2-g4 Rh7-h1+ 17.Kc1-b2
+- (3.47) Depth: 19 00:09:21 135mN
10...Rf8-f7 11.e3xd4 b6-b5 12.Qh4-g4+ Rf7-g7 13.Qg4-e6+ Kg8-h8 14.f4-f5 Ra8-f8 15.f5-f6 Rg7-c7 16.d4-d5 Rc7-h7 17.Nd2-e4
+- (4.05) Depth: 20 00:25:16 378mN
10...d4xe3 11.Qh4-g4+ Kg8-f7 12.Nd2xc4 Rf8-c8 13.Kc1-d1 Rc8xc4 14.Qg4-f5+ Kf7-g7 15.Qf5-f6+ Kg7-g8 16.Qf6-e6+ Kg8-h8 17.Qe6xc4
+- (3.69) Depth: 20 00:36:44 562mN
10...d4xe3 11.Qh4-g3+ Kg8-f7 12.Qg3xe3
+- (4.22) Depth: 21 01:03:57 1010mN

(Soares, Residencia 24.05.2007)