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ganstaman
♡ 45 ( +1 | -1 )
Endgame fun
I was playing a blitz game here some time ago and reached what I think is an interesting endgame (and by interesting I mean I'm upset that I'm up material but think I can't get more than a draw). I don't recall the position exactly (it's been a while), but this is close enough to be entertaining.
It's black to move. Ignoring that I will lose on time, how do you evaluate this position?
ganstaman
♡ 19 ( +1 | -1 )
Oh, one more thing I should point out. The board is facing the proper direction, so it's from white's point of view. White is close to promoting 2 pawns.
Still, it is black to move.
sf115
♡ 11 ( +1 | -1 )
white will win. Blacks best idea is to bring his king over to the A8 corner to capture the pawns
ganstaman
♡ 57 ( +1 | -1 )
White will win? That is one result that would very much surprise me.
Here's how the game continued (at least a bit of it) 1...Rxa6 2. Rxa6 Qxb7.
Would that position really be won for white? It still feels like a draw to me, but 7 pieces is too much for a free endgame tablebase (at least from what I have found so far).
So, maybe marching the king to the queenside pawns is good for white. But if it ever fails, ...Rxa6 should help out. Unless that is also lost for black, which I guess is half what I'm asking.
loeki544
♡ 32 ( +1 | -1 )
End game fun
If black is to move here, black will win.
There is a forced mate after
1. ... Ra1+
2. Nf1 Kf7
3. Rg6 (this forced else it is mate in 2 with Qg8+ and than Qg2 mate) Qh8
Now there is not much for white to play.
4. b8(Queen) Rxf1+
5. Kxf1 Qa1+
6. Qb1 Qxb1++
Any other then the pawn promotion wil loose, with 1 move less
loeki544
♡ 5 ( +1 | -1 )
Sorry for my post i set it up with the black pawn on f6, i now see it is on e5
loeki544
♡ 14 ( +1 | -1 )
I still think black wins after Kf7.
Black has to much active play.
I see no move for white to win.
g-file is to dangerous for white.
djole73
♡ 24 ( +1 | -1 )
Black is winning after Kf7 of course. Because after Kf7 black threat with Qg8+ or if white try to escape black have time to set up his queen because king is no more on 8 rank and white will not promote b pawn with pin.
ganstaman
♡ 25 ( +1 | -1 )
Hmmm, I have not thought of Kf7 before, but this all looks good. I'll just tell myself that I got the position wrong and this wasn't possible in the actual game ... :)
Anyway, after 1...Rxa6 2. Rxa6 Qxb7, is that drawn?
rallyvincent
♡ 26 ( +1 | -1 )
Hmm...
I would say that 1. ...Kf7 leads to a draw.
2. Nc2 (to prevent the possible chess on a1) Qg8+
3. Kf1, and white has no chess left.
I would suggest 1. ...Kh7.
Does sound irrational, but this leaves the diagonal a2-g8 open, e.g.
2. Nc2 Qg8+
3. Kf1 (Kh1 leads to mate) Qc4+
4. Ke1 (or Kg1 5. Rg5+ Kh2 6.Qf1 with mate following) Qxc2
OR
2. Kf1 Ra1+
3. Ke2 Qf4.
Rally V.
ganstaman
♡ 12 ( +1 | -1 )
rallyvincent : It's not 1...Kf7 that has been claimed to win (I don't think), but 1...Ra1+ and 2...Kf7.
rallyvincent
♡ 26 ( +1 | -1 )
On a quick shot
I'd say
1. Ra1+ Kg2
2. Kf7 Nf5
If the Queen moves, the Knight will prevent chess on the g-file or have the possibility of giving chess himself. But it's late, and I haven't thought this through to the end. Errors are made by myself, you are not allowed to copy them without permission...
Rally V.
gloomy_den
♡ 126 ( +1 | -1 )
on a slow shot
first of all, after 1...Rxa6 2. Rxa6 Qxb7 the game is a draw. This position would be a draw even without a knight, all white have to do is to keep the rook on a third rank (e3 pr g3 squares).
So black can force a draw anytime. But, in my opinion, black can try to win this position, primarily because of the weak white king. The first move is 1...Kf7 (black move his king to c7 and threaten to play 2... Qg8 3. Kf1 Ra1 4. Ke2 Ra2! - that's where pawn on e4 came handy). White will continue 2. Rc6, defending the king (white would have reply 5. Nc2 in the aforementioned line), and threatening Rc6-c8. But then black will change their plan and play 2...Ra1 3. Kh2 Qh8 4. Kg3 Qe5 and black are forcing a checkmate.
It is important to start with 1...Kf7 instead of 1...Ra1. On 1...Ra1 2. Kg2 Kf7 white has 3. Nf5, as rallyvincent pointed out. After 1...Kf7, however 2. Nf5 falls short after 2... Rxf5 3. a7 (hoping for 3...Qxa7 4. b8Q Qa1 5. Rb1=) 3...Qf4!! and white is losing after both 4. b8Q Qxf2 and 4. Rb2 Qg4 5. Kf1 Qd1
Another gimmick white might want to try is 2. Ng4 after which black use similar approach: 2...Rg5 3. a7 Rg4 4. Kf1 Qd8! White can promote either pawn to queen, but only to get a checkmate on the next move.
Yet another line - white is trying to escape. 2. Kf1 Ra1 3. Ke2 Ra2 4. Kf1 (4. Ke1 Qd8!) 4...Qh8 5. Kg1 Ra1 6. Nf1 Qg8 7. Kh2 Rxf1 8. b8Q Rxf2 9. Kh3 Qh7 10. Kg4 Qf5 11. Kg3 Rf3 with a checkmate.
So, in my opinion white is lost. I didn't check this solution on computer, so mistakes are possible.
gloomy_den
♡ 13 ( +1 | -1 )
short addition
on 2. Nc2, which was suggested as a cure against 1...Kf7, black can win in the following way: 2...Rg5 3. kf1 (3. Kh1 Qh8#) 3...Qd8! Now 4. b8Q Qd3 5. Ke1 Rg1 is a checkmate and after 4. Rb3 Qd1 5. Ne1 Qxb3 white can't promote their pawns.
ionadowman
♡ 171 ( +1 | -1 )
Interesting endgame...
... I rather like rallyvincent, his 1...Kh7, which seems marginally better than 1...Kf7 as it leaves the g8-a2 diagonal open for the Q after it goes to g8. The purpose of the King move is to vacate the g8 square, and indeed the whole g-file, for the queen, but also to obviate the immediate check if and when the White b-pawn promotes. It's a tempo saver.
What response can White make to 1...Kh7? Try, say, 2.Nc2 to stop Ra1+. 2.Nc2 Qg8+ 3.Kf1 (forced) Qc4+ 4.Kg2 Rg5+ 5.Kh3 Qf1+ 6.Kh4 Qg2 with a quick mate. If instead 4.Ke1 Qxc2 (5.b8=Q Ra1+ [-+]).
OK, 2.Nc2 was mooted just to see what threats Black has available.
How about 2.Kf1, to get off the g-file? 2.Kf1 Ra1+ 3.Ke2 Ra2+ 4.Ke1 Qf4 5.Nd1 Qd2+ 6.Kf1 Qxd1+ 7.Kg2 Qf3+ with mate looming. 4.Kf1 is no better: 4...Qf4 5.Nd1 e3 6.b8=Q e2+ 7.Kg2 (!) Qxb8 8.Rxb8 exd1=Q [-+].
Or, if 2.Kf1 Ra1+ 3.Kg2 Qg8+ 4.Kh2 Ra5 ought to bring a swift quietus.
Try 2.Nf1, with a view to blocking the g-file should Black check along it. 2...Rg5+ 3.Ng3 Rxg3+! 4.fxg3 Qxg3+ 5.Kf1 Qf3+ 6...Qe3+ and picks up the rook. The only alternative, after 2.Nf1 Rg5+ is 3.Kh1. This looks more promising: 3.Kh1 Qf4 4.Ng3! Qxf2 5.b8=Q Rxg3 which looks as though it should draw (e.g. 6.Qc7+ Rg7 7.Qh2+ [=])
4...Qf3+ 5.Kg1 seems to be no improvement for Black. Try then this: (2.Nf1 Rg5+ 3.Kh1) Rh5+ 4.Kg1! (4.Kg2 Qf4!) and it looks as though Black's rook might have to return to a5.
Very well, try another route: 2.Nf1 Ra1 3.Kg2 Ra2 threatening 4...Qf4. 4.Ng3 can be met by 4...e3; 4.Rf6 by 4...Qa7, rounding up the Q-side pawns. Worth a look, then...
I'll stop here, I think, and maybe explore further in another posting.
Just quickly, though, after 1...Rxa6 2.Rxa6 Qxb7 3.Rd6 followed by Rd5 seems to set up an impenetrable fortress: the rook forms a rampart Black king hasn't a prayer of breaking through, short of exchanging Q for R+N, with a drawn P ending in prospect. White could go after Black's exposed P, but his priority will be to protect the f-pawn, thus maintaining the foundations of that Maginot Line on the 5th rank.
Cheers,
Ion
ionadowman
♡ 53 ( +1 | -1 )
Oops! A blind spot...
...In that last posting I looked at 1...Kh7 2.Nf1?! Rxg5+ 3.Kh1 Qf5 4.Ng3 Qf3 5.Kg1 where I stopped, thinking that White's defences held. They don't, of course, owing to the line analogous to that following 3.Ng3. Here Black continues 5...Rxg3+ etc, picking up the rook on b6 and winning easily.
It transpires also that Black has another winning line alternative to 5...Qf5, namely the startling 5...e3!! 6.Nxe3 Qf5 is a killer, and 6.a7 e2!! ends White's resistance instanter.
Clearly 2.Nf1 is no good.
We have yet to examine other 2nd moves by White, such as 2.Ng4 or even 2.Nf5 (Rxf5 3.a7, say)...
;-)
ionadowman
♡ 138 ( +1 | -1 )
Once more unto the breach...
...dear friends, once more...
A couple of lines I have had a chance to examine:
1...Kh7
w
2.Ng4 Rg5 3.Rh6+ Kg7 4.Rh4 ... Now 4...Rg6! seems to win without trouble, as the White Q-side pawns must fall. But I like to force the issue: 4...Qf4! 5.a7 e3 6.b8=Q Qxf2+ 7.Kh1 Qxh4+ 8.Qh2 (forced, as 8.Kg1(or Kg2) Rxg4+ 9.Qg3 Qxg3+ and mate next). So: 8.Qh2 Qe1+ 9.Qg1 Qxg1+ 10.Kxg1 Rxg4+ 11.Kf1 Ra4 wins the K+R vs K ending. At move 6, capturing on e3 is no help to White: 6.fxe3 Qxe3+ 7.Kg2 Qxa7 with an easy win.
Does White have a useful rook move, then? Moving off the 6th rank won't do, as ...Rxa6 removes all White's chances.
That leaves 2.Rc6 or 2.Rf6
- 2,Rc6 Ra1+ 3.Nf1 Qg8+ 4.Kh2 Rxf1 and now 5.Rc2 Rg1 6.Rc7+ Kh6! 7.Rc6+ Kh5 8.Rc5+ Kh4 [-+]; the immediate 5.Rc7+ is similar, and 5.Rc8 Rxf2+ 6.Kh3 Qg2+ 7.Kh4 Rf4+ 8.Kh5 Qg6#
- 2.Rf6 covers f2, which might be useful. This turns out to be trickier than it looks: 2...Qg8+ 3.Ng2 (say) Rg5 4.Rf7+!! Kh8! (taking the rook allows White to promote at b8) 5.Kh1 Rxg2 6.Rf8! Qxf8! 7.Kxg2 Qb8 whence the BQ restrains White's advanced pawns whilst guarding the dark squares around Black's own pawn at least until the King can intervene.
Instead of 5.Kh1 White lunges for the queening squares: 5.a7!? Rxg2+ 6.Kf1 Rg1+ 7.Ke2 Qg4+ 8.Kd2 Qd1+ 9.Ke3 Qd3+ 10.Kf4 Qf3+ 11.Ke5 Rg5+ 12.Ke6 Qb3+ 13.Kf6 Rf5+ 14.Kxf5 Qxf7+ 15.Kxe4 Qxb7 16...Qxa7 etc. White can certainly vary (e.g. with 8.f3 or 8.Ke3 ) but it doesn't seem to help much.
What if White decides not to interpose e.g. 1...Kh7 2.Rf6 Qg8+ 3.Kf1 (you can see what happens if he goes to h1 or h2!) 3...Ra1+ 4.Ke2 Qa2+! 5.Nc2 (forced!) Qxc2+ 7.Ke3 Qd3+ 8.Kf4 Qf3+ 9.Ke5 Ra5+ 10.Kd6 Rxa6+ etc, with a straightforward win in prospect.
It seems that after 1...Kh7 White's outlook is pretty bleak.