Aug-13-20
 | | al wazir: I interchanged moves 29 and 30: 29...Rxa2+ 30. Kxa2 b4, etc. Does the order matter? |
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| Aug-13-20 | | goldfarbdj: <al wazir>: I think it does. Since White hasn't opened up the c3-square, Black doesn't have the line-opening 32. ... c3, and White doesn't have to allow it, but can instead play the blocking 31. Na3. If 31. ... bxa3 32. bxa3 it looks to me like White can use the open b-file at least as well as Black can. |
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| Aug-13-20 | | Walter Glattke: My line, playing at chessboard before clicking this 2nd website here, it was 29.-Rxa2+ 30.Kxa2 Qa6+ 31.Na4 b4 32.cxb4 Nxb4+ 33.Kb1 c3 34.Qf4+!? e5 35.dxe5 looking this now on website 2, 35.-c2+ really nice, that. A) 36.Nxc2 Qa2+ 37.Kc1 Rxc2# B) 36.Kc1 cxd1Q++ 37.Kxd1 Qf1+ 38.Kd2 Re8+ and Qd3# |
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| Aug-13-20 | | Walter Glattke: *31.Na3 |
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| Aug-13-20 | | Brenin: After 29 ... b4, can White defend with 29 ... a3, e.g. 30 bxa3 Nxa3? Does this give White time to reorganise his defences by Rc1, Qc2, etc? I don't see a clear win for Black, though he clearly stands better. |
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Aug-13-20
 | | agb2002: White threatens Qxh6.
Black can continue the attack and stop this threat with 29... b4: A) 30.Qxh6 Qa4 wins the rook on d1.
B) 30.cxb4 Rxa2+ 31.Kxa2 Qa4+ 32.Na3 c3
B.1) 33.bxc3 Nxc3+
B.1.a) 34.Ka1 Qxa3+ 35.Qa2 Qxa2#.
B.1.b) 34.Qxc3 Rxc3 followed by Qxa3 wins.
B.1.c) 34.Kb2 Nxd1+ 35.Kb1(a2) Nc3+ 36.Kb2 Qxb4+ wins (37.Kc2 Ne4+). B.2) 33.Qc1 Nxb4+
B.2.a) 34.Kb1 c3+ wins (35.Nxc2 Qa2#).
B.2.b) 34.Ka1 Qb3 35.Qb1 c2 36.Nxc2 Nxc2+ 37.Qxc2 Rxc2 38.Rb1 Qa4#. B.3) 33.Qe2 Nxb4+
B.3.a) 34.Kb1 c2+ 35.Nxc2 Rxc2 wins.
B.3.b) 34.Ka1 Qb3 35.Kb1 (35.Qb5+ Ka8 does not solve much for White) 35... c2+ as above. C) 30.a3 bxa3 followed by Ka8 with the idea of piling up heavy pieces on the a- or b-files. For example, 31.bxa3 Ka8 32.Qxh6 Nxc3 33.Nxc3 Rxa3+ 34.Kb2 Qb6+ 35.Kc2 (35.Kxa3 Qb3#) 35... Qb3+ 36.Kd2 Qxc3+ with a winning attack. |
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| Aug-13-20 | | Predrag3141: I got it, other than chosing 33 ... c2 instead of 33 ... Nxb4+ (as played). I wanted to prevent 34 Kb1 so 34 ... Qb3 forces White to give up his queen to prevent mate. But 34 Kb1 would have lost badly anyway, and preventing it was not worth taking the pressure off b2. |
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| Aug-13-20 | | stacase: The Rook sacrifice was an obvious choice. The rest was straight forward, although I strayed from the line and failed to see that 34...Qb3 threatened mate and wins - Duh! |
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| Aug-13-20 | | Walter Glattke: C) 30.a3 bxa3 31.bxa3 Ka8 with no 32.Qh6!?, maybe 32.Qa2 looks complicated. 32.-Qa6 33.Rc1 Rb8 34.f4 Qd5 35.Rh2 Rxb1+ 36.Kxb1 Rxa3 37.Qf2!? Qb5+ 38.Kc2 Ra2+ 39.Kd1 Rxf2 40.Rxf2 Qb3+ here black wins. Other moves are possible. |
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| Aug-13-20 | | sophiephilo: ah. got it. :). its a rare victory. |
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Aug-13-20
 | | beatgiant: I spent a lot of time looking at 30. a3 <Qa6> and convinced myself that it probably wins. But the engine thinks <agb2002>'s idea above 30. a3 <bxa3> is stronger. |
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Aug-13-20
 | | drollere: it turns out that the "silent" R on c8 has a lot to say. |
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| Aug-13-20 | | TheaN: Yeah I got the ideas here but was a bit sloppy. Convinced that <29....b4> was playable on account of 30.cxb4? Rxa2+! 31.Kxa2 Qa4+ 32.Na3, but here I settled on the somewhat straightforward 32....Qb3+ 33.Kb1 Nxb4 forcing 34.Qxb4+ Qxb4 -+ with a rather easy win, but 32....c3 is much better. As an alternative for White on move 30; perhaps, but not position-saving. Wasn't sure what to play after 30.a3. bxa3 looks good, but eyed at Qa4 too, which just seems to pile up without issue, but White may be able to have a playable game after 31.Rc1! preparing Qc2, so 31....bxa3 32.Nxa3 Qb3, because 33.Qc2? Rxa3+! 34.bxa3 Qxa3+ 35.Qa2 Qxc1+ -+, but after 33.Rhh1! Black doesn't have this and has no time to double up on the a-file. After 33....Kc7 34.Qc2 Rb8 ∓ Black is much better but not winning just yet. |
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| Aug-13-20 | | tatarch: <al wazir: I interchanged moves 29 and 30: 29...Rxa2+ 30. Kxa2 b4, etc.
Does the order matter?>
I did this too and no it doesn't work :(
As <goldfarbdj> pointed out white has Na3 which I missed and which stockfish says is a draw at best for black. 1) =0.00 (26 ply) 31.Na3 Qa4 32.Rc1 bxa3 33.Qc2 Nb4+ 34.cxb4 axb2+ 35.Kxb2 c3+ 36.Qxc3 Rxc3 37.Rxc3 Qd1 38.Rc2 f5 39.d5 exd5 40.Rf4 Qd3 41.Rc3 Qd2+ 42.Rc2 Qd3 |
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| Aug-13-20 | | mel gibson: I wasn't sure but I could see White was in a lot of trouble. Stockfish 11 says
29... b4
(29. .. b4 (b5-b4 ♖d1-c1 ♕c6-a6
♘b1-a3 b4xa3 ♖c1-b1 a3xb2+ ♖b1xb2+ ♔b8-a8 ♖h4-h1 f6-f5 ♖h1-c1 ♖a5-a3 ♖c1-c2
♖c8-h8 ♕d2-c1 ♕a6-a4 f2-f3 ♖h8-b8 g3-g4 ♖b8xb2 ♖c2xb2 ♘d5xc3 ♕c1-c2 ♘c3-d5
♕c2xa4 ♖a3xa4 ♖b2-c2 c4-c3 ♖c2-c1 ♖a4xd4 a2-a3 f5xg4 f3xg4 ♖d4-d2 g4-g5
h6xg5 h5-h6 ♖d2-h2 a3-a4 ♖h2xh6 ♔a1-a2 g5-g4 ♔a2-a3 f7-f5 ♖c1-g1 ♘d5-f6
♖g1-c1 ♘f6-e4 ♖c1-c2 ♔a8-b8 a4-a5 ♔b8-c7) +8.77/40 242) score for Black +8.77 depth 40 |
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| Aug-13-20 | | RandomVisitor: After 27...Ra5
click for larger viewStockfish_20081207_x64_modern:
NNUE evaluation using 20200812-2257.bin enabled. <46/72 08:09 0.00 28.a3 f5 29.Nb1> a6 30.Qc1 Qa4 31.Rhh1 Rh8 32.Rde1 Ka7 33.Re5 Qc6 34.Rhe1 Rb5 35.R1e2 Rb6 36.Re1 |
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| Aug-13-20 | | RandomVisitor: After 29.Qd2 Stockfish likes 29...b4, but also 29...Rxa2+
click for larger viewStockfish_20081207_x64_modern:
NNUE evaluation using 20200812-2257.bin enabled. <53/89 4:10:09 -10.32 29...b4 30.Rc1 Qa6 31.Na3 bxa3> 32.Rb1 Ka8 33.Rhh1 axb2+ 34.Rxb2 f5 35.Rc1 Ra3 36.Rcc2 Qa4 37.f3 Rb3 38.Kb1 Rxb2+ <52/75 4:10:09 -5.17 29...Rxa2+ 30.Kxa2 b4 31.Na3 Qa4> 32.Rdh1 Ka8 33.cxb4 c3 34.Qd1 c2 35.Qf3 c1Q 36.Rxc1 Rxc1 37.Rh1 Qc6 38.Rxc1 Nxb4+ 52/111 4:10:09 -3.04 29...Qa6 30.a3 b4 31.cxb4 c3 32.Qc1 Rxa3+ 33.Nxa3 cxb2+ 34.Qxb2 Rc3 35.Ka2 Qa4 36.Rb1 Rd3 37.Qb3 Rxb3 38.Rxb3 Qa6 |
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Kibitzing
sac: 30...Rxa2+