|Jul-04-19|| ||agb2002: Black has a rook and a knight for the bishop pair.|
White threatens to push the d-pawn.
The position of the white queen allows 31... Re4, to enable e4 for the knight:
A) 32.Bxe4 Qh1+ 33.Kf2 Nxe4+
A.1) 34.Kf3 Qh5+ 35.g4 Qxg4#.
A.2) 34.Ke2 Qxg2+ 35.Kd1 Rxd5 36.Qxd5 Nf2+ 37.Ke2 Qxd5 wins decisive material (38.Kxf2 Qxd2+).
A.3) 34.Qxe4 Qxe1+ (34... Qh4+ 35.g3 Qh2+ 36.Qg2 + -) 35.Kxe1 fxe4 with a won ending. For example, 36.d6 Rd5 37.Bb4 Kf8 38.Ke2 (38.d7+ Kg8 followed by Rxd7) 38... Ke8 followed by the attack against White's a-pawn.
B) 32.d6 Rxd4 33.exd4 Rd5 37.Bb4 Qd8 followed by Rxd6 + -.
|Jul-04-19|| ||al wazir: Black is an exchange up, so giving back the exchange is pretty safe. I should have realized that. But I decided to play 31...Ne4.|
|Jul-04-19|| ||patzer2: For today's Thursday puzzle, I went with 31...Re4! 32. Bxe4 Nxe4 -+ (-7.55 @ 32 ply, Stockfish 9 analysis of move 33.?).|
Comparing this line with the game continuation, it's clear 32...Nxe4 -+ is just as decisive as 32...Qh1+! -+ (-4.07 @ 27 ply, Stockfish 9 analysis of move 33.?).
P.S.: So where did Black go wrong? Black's game took a turn for the worse with 19. Kh1? Bxh2 ∓ (-1.34 @ 21 ply, Stockfish 9 analysis of move 19...?).
Instead, 19. h3 = (0.00 @ 24 ply, Stockfish 9 analysis of move 19.?) would have kept it level.
|Jul-04-19|| ||Once: <patzer2> Yes, me too! |
31... Re4 32. Bxe4 (what else? The queen is trapped) Ne4
I must admit I could not see a clear win from here, but what a knight outpost! That has to be an "... and wins" position.
|Jul-04-19|| ||areknames: Pretty spot on medium puzzle, not too easy nor too difficult. And yet two more GMs I had never heard of.|
|Jul-04-19|| ||saturn2: I noticed the rook has to be taken. Then like others I looked at 32...Nxe4 but thought 33. Re2 is good resistance.|
In the game line after
32...Qh1+ 33. Kf2 Nxe4+ you have to see 34. Kf3 leads to mate, which I did not.
|Jul-04-19|| ||Hercdon: <agb2002> actually in your A.2) line Stockfish has a quicker finish after 35.Kd1: 35 ... Qg4+ 36. Re2 Nf2+ 37. Ke1 Qg1#|
|Jul-04-19|| ||Hercdon: Hey happy Fourth of July to my American chess pals! We should all be able to pursue life, liberty and happiness. Now where is my morning tea?|
|Jul-04-19|| ||Ceri Evans: I also liked Re4 / Bxe4 / Nxe4. OTB the Qh1+ line seems a simple win.|
My main comment is after 19. h3.
I still prefer Black and SF agrees, although I would probably have played 19... Bg3 OTB.
click for larger view
Engine: Stockfish 10 64 Ceri (8192 MB)
by T. Romstad, M. Costalba, J. Kiiski, G.
35 4:06 -0.36 19...Qb8 20.Rfc1 Bh2+ 21.Kh1 Bg3 22.Qb4 Bf2 23.Rf1 Bh4 24.Kg1 Nh5 25.Rac1 Rfe8 26.f4 Nf6 27.Qb3 Rxc1 28.Rxc1 Rc8 29.Rxc8+ Qxc8 30.Kh2 Bf2 31.Qd1 Ne4 32.Bxe4 fxe4
34 4:06 -0.42 19...Bg3 20.Rac1 Qd7 21.Bb5 Qe6 22.Rc3 Rxc3 23.bxc3 f4 24.c4 fxe3 25.Qxe3 Qxe3+ 26.Bxe3 dxc4 27.Bxc4 Kg7 28.Rc1 Re8 29.Bg5 Rd8 30.Rd1 h6 31.Bd2 Nd5 32.Kf1 h5
34 4:06 -0.39 19...Qe7 20.Rae1 Qe6 21.Rc1 Bb8 22.Qb4 Bg3 23.Qb3 Rfe8 24.Rxc8 Rxc8 25.Rc1 Rxc1+ 26.Bxc1 Ne8 27.Bd2 Nc7 28.Qa4 Kg7 29.Kf1 Bh4 30.Ke2 h5 31.Kf1 Qd6 32.f4 Qe6
best move: Qc7-b8 time: 4:06.734 min n/s: 14.493.793 nodes: 3.576.242.202
|Jul-04-19|| ||TheaN: With Black being up an exchange (somewhat rare for CG puzzles) it becomes apparent we can throw it back with interest. This suggests <31....Re4!>.|
Typical here is that the queen's trapped, and White has no alternative in taking either rook as White was already down an exchange, effectively going Q v piece down (which is lost in nearly all instances).
However, after <32.Bxe4 Qh1+!> I'm willing to believe Nxe4 is just as strong but this is entirely forced. <33.Kf2 Nxe4+> Black poses another dilemma on White.
<34.Ke2> is effectively worse I'd say, but the alternative <34.Qxe4 Qxe1+!<>> allows Black to desperado the queen leading to <35.Kxe1 fxe4 36.d6 Rd5 37.Bb4 f5 -+<>> and White has no stakes in the endgame whatsoever.
However after <34....Qxg2+ 35.Kd1 Qg4+ 36.Re2 Ng3 -+> Black essentially forces the same trade off and White is lost.
|Jul-04-19|| ||TheaN: Oh, and then I miss the coup de grace with 36....Nf2+! 37.Ke1 Qg1#. Oh well. 36....Ng3 ought to prompt resignation as well :>|
|Jul-04-19|| ||rudiment: First Thursday I've gotten in ages. Re4 and White's Q is momentarily trapped, leading to a few forcing lines that at worst leave Black with a small but significant material advantage. |
I didn't find the exact game line - my Qh1 always came a bit later - but I'm chalking this down as a success.
Have I gotten worse or have the puzzles gotten harder?
|Jul-04-19|| ||patzer2: <Once><I must admit I could not see a clear win from here, but what a knight outpost!> Me Too! I figured, after 31... Re4 32. Bxe4 Ne4, Black would bring the Rook to c2 and make the position miserable for Black, but I didn't visualize a clear, winning combination.|
P.S.: Sorry one good team had to lose in the USA vs England Women's World Cup semifinal. If England had made their penalty kick and VAR had not found Ellen White offside, the Lady Lionesses could just as easily have been in the championship versus the Netherlands.
|Jul-04-19|| ||thegoodanarchist: Like the Elton John song says,
<He shall beat Levon>
|Jul-04-19|| ||zb2cr: I saw the initial move and follow-up, but I did not foresee the possibility of Whit giving up his Queen. So, I would say, half-credit for me.|
|Jul-04-19|| ||NBZ: I worked backwards on this one, which is how I imagine White also figured out Re4. Black would like to play 31. ... Qh1+ 32. Kf2 Ne4+, but 33. Bxe4 stops this idea. So we would like to get rid of the B on d3. Thus 31. ... Re4! comes to mind: the White queen is effectively trapped in mid-board, and so 32. Bxe4 must be played; but now Black can play 32. ... Qh1+ 33. Kf2 Nxe4+ and if 34. Kf3 Qh5+ is curtains.|
Aha but what about 33. ... Nxe4+ 34. Qxe4? Then Black has to play the intermediate move 34. ... Qxe1+ 35. Bxe1 fxe4 and the RvB ending should be winning for Black.
All of this is elegant and satisfying enough that I admit I never even considered the simple 32. ... Nxe4! after 31. ... Re4 32. Bxe4. Now 33. ... Qf2+ is threatened so 33. Rf1 (or Re2) have to be played; but 33. ... Rc2 is utterly deadly.
Which makes this a nice illustration of both the benefits and dangers of schematic thinking: I was able to find the idea of Re4, but could not step outside the box to see that after Bxe4, Black should forget about making Qh1+ work and instead play the simple Nxe4 setting up a new set of threats.
|Jul-04-19|| ||NBZ: < patzer2: <Once><I must admit I could not see a clear win from here, but what a knight outpost!> Me Too! I figured, after 31... Re4 32. Bxe4 Ne4, Black would bring the Rook to c2 and make the position miserable for Black, but I didn't visualize a clear, winning combination. >|
I believe your Rc2! is indeed the winning idea. There are 2 lines to look at after 31. ... Re4 32. Nxe4 (recognizing that Qf2+ must be stopped):
A] 33. Rf1 Rc2 (threatening Rxd2) 34. Bc3 Nxc3 35. bxc3 Qg3 and Qxg2# is unstoppable.
B] 33. Re2 Rc2 and now Black has the unstoppable threat of 34. ... Rxd2 35. Rxd2 Qe1+.
|Jul-04-19|| ||patzer2: <NBZ> Thanks for the deeper analysis of 31... Re4 32. Bxe4 Ne4 -+ with the idea of bringing the Black Rook to c2.|
P.S.: By the way, I have a correction.
I meant to write "I figured, after 31... Re4 32. Bxe4 Ne4, Black would bring the Rook to c2 and make the position miserable for <White>, but I didn't visualize a clear, winning combination."
|Jul-05-19|| ||agb2002: <Hercdon: <agb2002> actually in your A.2) line Stockfish has a quicker finish after 35.Kd1: 35 ... Qg4+ 36. Re2 Nf2+ 37. Ke1 Qg1#>|
Nice maneuver. Thank you!