White to move. How should White proceed?
1K5B/2n1p2P/3PP3/8/7p/8/k1P2P1p/5b2 w – – 0 1
Dall Ava, 1946
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White to move. How should White proceed?
1K5B/2n1p2P/3PP3/8/7p/8/k1P2P1p/5b2 w – – 0 1
Dall Ava, 1946
E.g. not:
1. Ba1? h1=Q!
2. h8=Q Qa8+!
3. Kxc7 Qxh8
black wins.
Also not:
1. dxc7? Ba6!!
2. c8=Q Bxc8
3. Ba1 h1=Q
threating Qb7#
4. Kxc8 Qa8+
black wins.
Better looks:
1. d7!! Nxe6 (deflected from supporting Qa8+)
2. Ba1! h1=Q (Kxa1 h8=Q+ looses directly)
3. h8=Q
now threating Qb2#, whereas blsck has no direct threat, and his pieces are clumsy.
3. … Ka3
4. Qc3+ Ka4
5. Qb3+ Ka5
6. Bc3+ Ka6
7. Qb7#
1. d7! h1=Q (Nxe6 Ba1 seems to loose quickly)
2. d8=Q
should also clearly loose for black, since Qa8+ Kxc7 Qxd8 Kxd8 just looses material and is of no help. White will end up with an extra queen.
This is way too hard.
Kxc7
Maybe:
1. Ba1 h1=Q 2. h8=Q. The point with 1. Ba1 is that white now has the threat 3. Qb2#, so that black has no time to start a counterattack. Some possibilities:
2… Na6+ 3. Ka7 and no more checks are possible.
2… Qa8+ 3. Kxc7 Qa7+ (Qxh8 Bxh8 is hopeless) 4. Kd8 Qb8+ 5. Kxe7 Qa7+ 6. d7, and black is lost.
the study is cooked on move 3
1.dxc7 seems to fail to 1. … Bh6 preventing white pawn from queening.
Only hope I can see is the odd looking 1.Ba1 because then,
if 1…Kxa1, 2. h8=Q+ followed by 3. Qxh4 preventing black from queening the h2 pawn.
if 1…h1=Q, 2. h8=Q and I can’t see how Black can stop mate in b2.
Black can try 2. Na6+ but 3. Ka7, keeping white King on a dark square and Black runs out of checks.
If 2… Ka3 then 3. Qa2+ followed by mate in a3.
Looks quite good…
I am thinking the Anonymous commenter might be right. What is the goal of white in this position? Draw or win? The obvious thing to look at first, though I felt right from the start that it couldn’t be a solution, is to capture at c7 with the d-pawn:
1. dc7 Ba6! (only move)
And now what for white? He can’t queen at c8 to win black’s bishop since black will queen himself, and check from a8 to then effectively promote the backward h-pawn. However, when I reach deep enough into the ending, it is messy and unclear to me. Most of this seem pretty straightforwardly forced, so I don’t think I am missing anything:
2. c8Q Bc8
3. Kc8 h1Q
4. Bg7 Qa8
5. Kd7 h3
6. Ke7 h2
7. h8Q Qh8
8. Bh8 h1Q
Is this drawn or lost for white? I can’t easily tell. I do know that if white’s f and c-pawns weren’t on the board, this is a known win for black, but if the king and pawn were on d7 and e7 instead, it is a draw. So, the question is, can black win the two flanking pawns before white advances the king and e-pawn? I really don’t see how. Continuing:
9. Be5
Planning to play f4, and a later c3. Can black muck up this plan?
9. …..Qf3 (blocking f4)
10.Kd7 Qd5 (Qf3 11.e7=)
11.Bd6 Qb5
12.Kc7
And now what for black? I just don’t see a winning line for black. I am pretty sure he can draw by repetition, but no more than that. So I have to conclude that white must have a move to win. I have an idea in mind, and will cover it in my next comment.
In my previous comment, I covered the ideas in the line where white captures the knight with dxc7. The move that actually first catches my attention is 1.Ba1, however. The idea is pretty simple- it clears the h8 square and entices black to put his king on a1 where the queening occurs with check allowing white to capture at h4 and h2 sequentially?
1. Ba1 h1Q
If 1. …Kxa1?? 2.h8Q+ is followed by Qxh4 and Qxh2/h1 since black doesn’t have enough time to play Bg2 to guard h1. So, black must queen immediately:
2. h8Q Qa8 (what else?)
3. Kc7
And, now, I question if white has more than a draw here? I see basically two lines here:
3. …..Qh8
4. Bh8 ed6
5. e7 Bb5
6. c4
I don’t think 6.Kd6 changes much. Continuing:
6. …..Ba4 (or Be8)
7. Kd6 and this is clearly a win for white even with the bishops of opposite color- white is just going to march the c-pawn forward and eventually overload black’s bishop, while white’s own bishop holds up the h-pawn from e5. However, black does not need to cooperate by taking at h8 at move 3:
3. …..Qa3 (guards b2)
Can white pull a win out now? The main problem I see is the exposed nature of white’s king. For example, if white pushes d7 here, black checks from a5, and the king will have to avoid the white squares just to keep from being mated by the queen/bishop combo- so black will get a draw at a minimum by repetition. So, can white win by forcing the exchange at b2? From the top:
1. Ba1 h1Q
2. h8Q Qa8
3. Kc7 Qa3
4. Qb2 Qb2
5. Bb2 ed6
The fly in the ointment (or, one of the flies in the ointment), or not? Of course, 5. …Kb2?? loses instantly to d7. However, now, I see a very messy position:
6. Bc1
For one move, the e5 square is covered by black’s pawn, so the bishop must not only save itself, but find a way to cover h2 in two moves- Bc1 is the only way. White can transpose here with his own pawn push of e7, but after Bb5, I think we are going to see a full-fledged transposed line. Continuing:
6. …..h3
7. Bf4 d5
8. Kc6
To try to prevent Bb5. Continuing:
8. …..Ka3 (heading for a4)
9. e7 Ka4
10.Kd5 Bb5
And, I am fairly certain this is won for white, but not 100% sure. My concern is that black might be able to win the c and f-pawns while sacrificing the bishop for the e-pawn when forced to. I think the best plan is to put the bishop on h2, and push the f-pawn immediately- I think that will win. All in all, a very tough problem, not one I am convinced is solved.
probably not the right combo, but I would play d7, Nxe6, Be5+, winning the h-pawn.
1. Ba1 (Seems to work. Tonight I don’t have much time to analyze thoroughly)
1…h1=Q (1…KxB 2.h8=Q wins)
2.h8=Q Qa8+ 3.KxN Qa7+
(3…QxQ 4.BxQ exd 5.e7 Bb5 6.c4 Be8 7.Kxd6 h3 8.Be5 and Black should loose his Bishop for one of the advanced pawns.)
4.Kd8 Qb6+ 5. Kxe7 and White’s advanced pawns are decisive.
1. Ba1! looks like winning to me
Ba1 seems to win.
@pht:
1. Ba1? h1=Q!
2. h8=Q Qa8+!
3. Kxc7 Qxh8
Black does not win here!
4. Bxh8 exd6 (best move I can see)
5. e7 Bb5
6. Kxd6 1-0
@pht:
Also, in your line why not:
3. … Qh2+ etc.
And in any case,
7. Qb7+ is not checkmate!
7. … Qxb7