White to move. Can you find the winning plan? No computer please!
This is a very difficult puzzle! Enjoy!
Source: Chess Today
Study of the Year 2007
by IM Yochanan Afek
The following study was selected in Yurmala, Latvia at the annual congress for chess composition.
Chess Daily News from Susan Polgar
1) Nf3+ Kh3
2) Ng5+ Kh2/g2,
3) Bxc5+
looks like a clear win.
So I’m wondering if there is some mating net/ pattern I don’t know.
oh!!! I see the hole in my plan!
Can’t wait to see the correct solution.
Wow this is a killer.
1. Nf3+ looks obvious, it forces Black to reply Kh1 since Kg2 loses immediately to 2. B:c5+ and Kh3 to 2. Ng5+ forcing the king back to the 2nd rank and the deadly discovered check.
After 1. Nf3+ Kh1, it would be nice to move the B and create a mate threat. But Black has many threats – Qc7+, Qf7+ and, most importantly Qa4+ picking up the Rc2.
Candidate moves seem to be 2. Kg3, 2. Ke3, and the weird piece sacrifice 2. Bd4 – moving the K to the 5th rank seems pointless – Kf5 loses to Qh7+, Ke5 runs into big trouble after Qf7 because the K can no longer get back to guard either minor piece, and Kg5 allows Qe7+ threatening Qe4 forking the N and R.
2. Kg3 Qg7+ forces the K back to f4 since moving the K to the h-file allows Qh7+ picking up the R. But after 3. Kf4 Qf6+ forces the K to e3 because of the threat of Qg6+. But Black plays d4+ Ke2 (protecting the N temporarily) d3+ and the N falls.
If instead 2. Ke3 d4+ and white has no good square for the K – d2 allows Kg2 winning a piece, d3 allows Qa6+ forcing the K to choose among d2 allowing the K fork, e4 allowing Qg6+ winning the R, and Rc4 walking into a suicidal pin and allowing the K fork.
So, incredibly enough, Bd4 seems like the only sane (!?!) move. Since this has already killed my evening, I will post this much and see what the answer is tomorrow.
I think I got it after a bit of trial and error. The real key to this was finding the way to block the check from a4:
1. Nf3 Kh1
If Kg2, then Bc5 wins easy. Also, Kh3 allows 2.Ng5 and the king goes right back to the 2nd rank for the discovered check Bc5 again. Continuing:
2. Bd4!
The key to the puzzle, I think. Stopping the check from f7 is fruitless, I think, but stopping the one from a4 is critical, and this is the only move I can find that does that. The bishop can’t be taken since the threat is Rh2#. Continuing:
2. …..Qf7
Black can’t protect h2 from h7- white just plays 3.Rc1 Kg2 4.Rg1 Kh3 5.Rg3#. The other alternatives, I will append below. They are a bit complicated for a parenthetical note. Continuing:
3. Ke3 cd4
There is nothing better now. The king is going to f2 even on Qe6+, and remember, white is still threatening Rh2# here, and h2 still can’t be guarded from h5 or h7 since white will play Rc1+ followed by Rg2 and, now, Rh1 to win the queen. Continuing:
4. Kf2
With the threat of Rc1#. Black can’t block this successfully, has no checks on the king, and can only guard the c1 square from f4:
4. …..Qf4
Now we come the second critical part of this puzzle. Black is threatening Qe3 (if white plays 5.Re2) and Qc1 (guarding against moves like 5.Rb2 and 5.Ra2). Remember, black would be happy to give up the queen for the rook. Finally, if white plays 5.Rc8, black checks from e3 driving the king to g3, and then puts the queen on h6: [5.Rc8 Qe3! 6.Kg3 Qh6
7.Kf2 Qe3 etc.]. So, white must prevent these threats of Qc1 and Qh6, so…
5. Rc6!
A really, really clever puzzle. One of the best quiet moves I have ever seen in a chess composition, and I have seen literally 10,000s of these puzzles over 3 decades. Black now has a dilemma. His king can’t move, the queen can’t leave the c1/h6 diagonal unless it is to check the white king. Let’s just play through the options to see what white has in store:
5. …..Qe3
6. Kg3
And the black queen has no safe square on that c1/h6 diagonal but the one she sits on, and she can’t check the king (a motif you see in over the board chess quite often- a knight next to his king guarding against queen checks along the diagonals and files/ranks-I played a blitz game just yesterday where such a guarding arrangement served me well) so d3 must be played here:
6. …..d3
7. Ra6!
The queen is now going to get outmanevered. 7.Ra6 is threatening 8.Ra1 followed by mate. The only move where black doesn’t give up the queen for the knight to stop this is …
7. …..Qc1
8. Ra7
Keeping the threat on a1 and now on h7 and the queen can’t prevent both.
So, let’s back up to move 5 to see if black had better a better option:
5. …..d3
6. Rc8
Previously, this move didn’t win since black could first check safely from e3 then put the queen on h6 ready to harrass the white king endlessly, but that option was ended when black pushed the d-pawn at move 5. Now there is no answer to the twin threats of Rh8 and Rc1.
Since it is late for me, I will write up my notes on the options at move 2 for black tomorrow. They are important to not leave as loose ends.
Haven’t figured it out yet, but at first sight i would look for something like: Nf3+ forcing Kh1. If not, the Q is lost. And now either Bg1 immobilising the K and threatening mate at h-file. The K must run to a safe not-checkable square (f1/2). Or, maybe better, Bg3 where the N and B now form a sort of wall for the K to hide. The R mates on the first row. The Q can check some more, but it will stop caus he’s hinderd by his own pawns. I guess he’ll have to give the Q for R, leaving an end game where white mates with B&N. Nice plan if i may say, but is it possible…hahaha.
Everything seems to start with Nf3+. Got two scenarios down so far. Working on 3rd where K retreats to h1 in response to Nf3+.
Scenario 1:
Nf3+, Kg2
Bg3+,
If Kh3, Ng5#
If Kh1, Rh2#
If Kf1, Rf2#
Scenario 2:
Nf3+, Kh3
Ng5+, Kg2
Bg3+, Kg1
Nf3+,
If Kh1, Rh2#
If Kf1, Rf2#
Everything seems to start with Nf3+. Got two scenarios down so far. Working on 3rd where K retreats to h1 in response to Nf3+.
Scenario 1:
Nf3+, Kg2
Bg3+,
If Kh3, Ng5#
If Kh1, Rh2#
If Kf1, Rf2#
Scenario 2:
Nf3+, Kh3
Ng5+, Kg2
Bg3+, Kg1
Nf3+,
If Kh1, Rh2#
If Kf1, Rf2#
In my first comment, I outlined a plan to pin black’s king on h1 using the the knight check from f3 and moving the bishop off the second rank:
1. Nf3 Kh1
2. Bd4
I think I showed conclusively that black loses in all variations after checking from f7 with the queen. Left undiscussed were the variations where black checks from c7 or b8. I will now cover those.
2. …..Qb8
3. Be5!
I think this is the only winning move. When the king moves off the b8/h2 diagonal, black’s queen will be covering h2 to prevent the immediate mate, so the bishop will fall without much compensation in position: [3.Kg4 cd4=]; or [3.Ke3 cd4 (or Qb3 better?) 4.Kf2 Qb1!= where the rook can’t leave the 2nd rank without allowing the black queen to check from b2]. Finally, white can’t block the check from b8 with the knight: [3.Ne5?? cd4 and now the knight is pinned, and white can’t play Kg3 to reestablish a mating threat, and likely has a losing position]. Continuing:
3. …..Qf8 (Qb4 4.Kg5+-)
4. Ke3! Qh6
Or [4. …d4 5.Kf2 Qh6 6.Ra2 Qc1 (or 6. …Qe3 7.Kg3+-) 7.Kg3+-]. Continuing:
5. Kf2
And, as in the first comment, the queen has no safe square to move to on the critical c1/h6 diagonal, so a pawn must be moved:
5. …..d4 (c4 no better)
6. Ra2
Threatening Ra1#:
6. …..Qc1 (Qe3 7.Kg3+-)
7. Kg3 and the black queen can’t prevent both Ra1# and Rh2#.
Finally, back at move 2, things are different still if black checks from c7:
2. …..Be5
Last night, I had thought this move couldn’t win like in the line above since black could guard the immediate mate from h7 (in the line above, the similar guard from h8 isn’t possible because of the bishop), and I am still not 100% sure, but will outline what I view as the problem and what I think is the solution this morning:
3. …..Qh7 (Qf7 4.Ke3+-)
4. Rd2! Qh6 (alternatives follow)
5. Kg3 Qg6
Of course, black can take the rook here, but the ending is lost prima facie, and isn’t all the difficult in the position. Continuing:
6. Kf2 Qg2 (Qb1 7.Re2+-)
7. Ke3 d4 (what else now?)
8. Kf4 Qh3 (nothing better)
And this is where I got stuck last night, and abandoned the block with the bishop from e5 at move 3. However, this morning, it occurred to me to play the bishop to f6:
9. Bf6 Qh6 (c4/d3 10.Bh4+-)
10.Kg3 Qg6 (what else?)
11.Bg5 Qd6
12.Kf2 and the mate can no longer be prevented.
So, in the line above, we need to back up to move 4 where black still had some alternatives. From the top:
1. Nf3 Kh1
2. Bd4 Qc7
3. Be5 Qh7
4. Rd2 Qe4
5. Kg3 Qg6 (what else?)
6. Kf2 Qg2 (Qb1 7.Re2!+-)
7. Ke3 d4 (what else?)
8. Kf4 and we saw this position above, and it was lost.
And finally, I think white can avoid this complicated line after 3.Be5 by playing 3.Ne5 instead:
1. Nf3 Kh1
2. Bd4 Qc7
3. Ne5
This is different than the line where black has checked from b8 in that, with the queen on c7, the c-pawn is pinned to the queen by the rook and cannot capture at d4 any longer. Also, by blocking with the knight, white has taken away the check from f7. Also, the black king is still immobilized on the h1 square. Black can try to unpin the c-pawn by moving the queen, but I don’t any move will save black here- white is threatening Kg3 followed by mate on the first rank:
3. …..Qb8 (keeps knight pinned)
4. Rb2! Qf8 (alternatives follow)
5. Kg3 Qg7 (nothing better)
6. Ng4!
And white has both Rb1 and Rh2 as mate threats. Black can’t check from c7 since white blocks with Be5. Black must either guard both h2 and b1 from h7, or he must take the bishop:
6. …..Qh7
7. Rd2 Qc7 (nothing better now)
8. Be5 and the mate can no longer be prevented. Or at move 6:
6. …..Qd4
7. Nf2! Qf2 (Kg1 8.Rb1+-)
8. Kf2 and mate must follow here within a few moves.
All in all, this was really great puzzle. One of the best I have seen posted here in the 5 years I have been coming here.
Everything seems to start with Nf3+. There are three possible responses: Kg2, Kh3, and Kh1. I’ve provided a scenario for each response.
Scenario 1:
Nf3+, Kg2
Bg3+,
If Kh3, Ng5#
If Kh1, Rh2#
If Kf1, Rf2#
Scenario 2:
Nf3+, Kh3
Ng5+, Kg2
Bg3+, Kg1
Nf3+,
If Kh1, Rh2#
If Kf1, Rf2#
Scenario 3:
Nf3+, Kh1
Rc1+, Kg2
Nh4+, Kh3
Rh1#
Brilliant composition indeed!
Alas, Matous died a few months ago.
White’s winning plan is to create a mating net to blacks king:
1. Nf3+! Kh1!
( 2… Kh3?? 3. Ng1+! Kh2 (or 3…Kg2) 4. Bxc5+ Kxg1 5. Bxa6 wins Queen +-)
( 2… Kg2?? 3. Bxc5+ wins queen)
2. Bxc5! ( threatening mate and attacking queen ) Qa4+! 3. Nd4! ( protects rook and blocks check ) Qd8
( 4. Nf3?? Qe4+ loses rook -+ )
4. Rd2! Qf7+ 5. Kd3! Qd8+ 6. Kf2! Qf7+ 7. Nf3! with mate to follow with Rd1 unless black sacrifices queen on f3 in which case white has winning endgame +-
Marcelo