1. Bd4 Kd2 (or lose to c4) 2. c4 Kd3 3. c5 Kd4 4. c6 a2 5. c7 a1(Q) 6. c8(Q) with a draw.
So, my first thought is that we are looking for a bishop move that leaves him within one move of a safe square on the a1/h8 diagonal. I can only imagine this move has to be either Bf4 or Bg5. Let’s look at both:
1. Bf4 a2
The alternative was to attack the bishop with Kf3, but this will allow the bishop to go to c1 and b2, and white will be able to push the pawn if the black king returns to e2, and if the king goes to e3, c4 still wins as the bishop and the pawn will combine with the white king to hem the black king in: [1. …Kf3 2.Bc1 a2 3.Bb2 Ke3 (or 3. …Ke4 4.Kg5 Kd5 5.Kf5 Kc4 6.Ke5 wins for white) 4.c4 Ke4 5.Kg5 and black is in zugzwang]. Continuing from move 1 above:
This is the only move to hold. If black tries the other approach of Kc4, he will lose to a deadly skewer after the pawns queen: [4. …Kc4?? 5.c6 Kd5 6.c7! Ke5 7.c8Q a1Q 8.Qh8+ Kanywhere 9.Qxa1+-]. With Ke4, white cannot prevent black from playing Kd5 and winning the c-pawn since he must move the bishop immediately.
So, I think we should already see the weakness of white’s very first move in comparison to Bg5. In the line above, bishop is forced to the a1/h8 diagonal at e5, and the black king’s attack on the bishop at move 4 seals the c-pawn’s fate. However, one should easily see that with 1.Bg5, the bishop will be sitting at f6, and out of reach of the black king for one additional move, and one additional move is all white needs. Let’s play it out:
1. Bg5 a2 (I will cover Kf3 below) 2. Bf6 Kd2
As before, black cannot play moves like Ke3 or Kf3 trying to get at the c-pawn: [2. …Ke3 3.c4 Ke4 4.Kg5 and the black king is forced back, or forced to queen and lose the a-pawn and the game, too]; or [2. …Kf3 3.c4 Kf4 4.Kg6 (not 4.c5? Kf5! 5.Kg7 Ke6!) 4. …Ke4 5.Kg5+-]. Continuing:
3. c4 Kd3 (what else?) 4. c5
And we have reached the analogous position seen in the 1.Bf4 line, but now white has a tempo in hand because the black king has no attack on the bishop from e4, and white will queen his pawn and prevent black from keeping his new queen. Continuing:
And, one last loose thread- in the line above, black could try 1. …Kf3, but this is futile:
1. Bg5 Kf3 2. Bc1
I think white wins with 2.Bf6, too: [2.Bf6 Ke4 3.Kg5 Kd5 4.Kf4 Kc4 5.Ke4 and the black king can’t get at the c-pawn before white’s king can support it]. Continuing:
2. …..a2 3. Bb2 Ke4 (Ke2/3 4.Kg5+-) 4. Kg5 and we have already seen that the black king can’t approach due to the closure of a3, b3, c3, and d3 by the bishop/c-pawn combo. White wins easily as before.
White stops the king from approaching the pawn from the front and if Black tries to approach the pawn from the side or rear White utilizes its first move option for the pawn moving up 2 squares 1.Bg5 Kf3 2.Bf6 Kg4 3.Kg6 Kf4 4.Ba1 Ke4 5.Kf6 Kd5 6.Kf5 Kc4 7.Ke4 Kc5 8.Kd3 Kb4 9.Kd2 Kc4 10.Kc1 Kb4 11.Kb1 Ka4 12.Ka2 Kb4 12.Be5 Ka4 13 Bc3 K5 14. Kxa3 wins
1 Bc1 should win the game as white should be able to march the pawn to the 8th rank.
The following don’t work:
Line 1:
1. Bd4 Kd2
2. c4 Kd3
3. c5 Kxd4
4. c6 a2
5. c7 a1(q)
6. c8(q)
white is a tempo behind for Qh8+
Line 2:
1. Bc1 Kd1
2. c4 Kxc1
3. c5 a2
0-1
—
What looks like working is:
1. Bg5 a2 (… Kd1 2. c4)
2. Bf6 Kd2
3. c4
1-0
First, let’s dispense with the “obvious” move:
1. Bd4 Kd2 (or lose to c4)
2. c4 Kd3
3. c5 Kd4
4. c6 a2
5. c7 a1(Q)
6. c8(Q) with a draw.
So, my first thought is that we are looking for a bishop move that leaves him within one move of a safe square on the a1/h8 diagonal. I can only imagine this move has to be either Bf4 or Bg5. Let’s look at both:
1. Bf4 a2
The alternative was to attack the bishop with Kf3, but this will allow the bishop to go to c1 and b2, and white will be able to push the pawn if the black king returns to e2, and if the king goes to e3, c4 still wins as the bishop and the pawn will combine with the white king to hem the black king in: [1. …Kf3 2.Bc1 a2 3.Bb2 Ke3 (or 3. …Ke4 4.Kg5 Kd5 5.Kf5 Kc4 6.Ke5 wins for white) 4.c4 Ke4 5.Kg5 and black is in zugzwang]. Continuing from move 1 above:
2. Be5 Kd2 (only move)
3. c4 Kd3 (only move)
4. c5 Ke4!
This is the only move to hold. If black tries the other approach of Kc4, he will lose to a deadly skewer after the pawns queen: [4. …Kc4?? 5.c6 Kd5 6.c7! Ke5 7.c8Q a1Q 8.Qh8+ Kanywhere 9.Qxa1+-]. With Ke4, white cannot prevent black from playing Kd5 and winning the c-pawn since he must move the bishop immediately.
So, I think we should already see the weakness of white’s very first move in comparison to Bg5. In the line above, bishop is forced to the a1/h8 diagonal at e5, and the black king’s attack on the bishop at move 4 seals the c-pawn’s fate. However, one should easily see that with 1.Bg5, the bishop will be sitting at f6, and out of reach of the black king for one additional move, and one additional move is all white needs. Let’s play it out:
1. Bg5 a2 (I will cover Kf3 below)
2. Bf6 Kd2
As before, black cannot play moves like Ke3 or Kf3 trying to get at the c-pawn: [2. …Ke3 3.c4 Ke4 4.Kg5 and the black king is forced back, or forced to queen and lose the a-pawn and the game, too]; or [2. …Kf3 3.c4 Kf4 4.Kg6 (not 4.c5? Kf5! 5.Kg7 Ke6!) 4. …Ke4 5.Kg5+-]. Continuing:
3. c4 Kd3 (what else?)
4. c5
And we have reached the analogous position seen in the 1.Bf4 line, but now white has a tempo in hand because the black king has no attack on the bishop from e4, and white will queen his pawn and prevent black from keeping his new queen. Continuing:
4. …..Ke4
5. c6 Kf5
6. c7! Kf6
7. c8Q a1Q
8. Qh8 Kanywhere
9. Qa1 wins.
And, one last loose thread- in the line above, black could try 1. …Kf3, but this is futile:
1. Bg5 Kf3
2. Bc1
I think white wins with 2.Bf6, too: [2.Bf6 Ke4 3.Kg5 Kd5 4.Kf4 Kc4 5.Ke4 and the black king can’t get at the c-pawn before white’s king can support it]. Continuing:
2. …..a2
3. Bb2 Ke4 (Ke2/3 4.Kg5+-)
4. Kg5 and we have already seen that the black king can’t approach due to the closure of a3, b3, c3, and d3 by the bishop/c-pawn combo. White wins easily as before.
Hi Susan Polgar,
Well,as there isn’t any specified number of moves for mating – This will be,the cake walk for white to win the game.
Example
=======
1.Bg5 Kd2
2.c4 Kd3
3.c5 a2
4.Bf6 Kc2
5.c6 Kb1
6.c7 a1(Q)
7.B*Qa1 K*Ba1
8.c8(Q)Kb2
9.Kg5 Kb3
10.Kf4 Kb4
11.Ke3 Kb5
12.Kd3 Ka5
13.Qb8 Ka6
14.Kc4 Ka5
15.Qb5++ Mate
White wins the game [ Variations exist ]
By
Venky [ India – Chennai ]
White stops the king from approaching the pawn from the front and if Black tries to approach the pawn from the side or rear White utilizes its first move option for the pawn moving up 2 squares 1.Bg5 Kf3 2.Bf6 Kg4 3.Kg6 Kf4 4.Ba1 Ke4 5.Kf6 Kd5 6.Kf5 Kc4 7.Ke4 Kc5 8.Kd3 Kb4 9.Kd2 Kc4 10.Kc1 Kb4 11.Kb1 Ka4 12.Ka2 Kb4 12.Be5 Ka4 13 Bc3 K5 14. Kxa3 wins
1…Bd4 will stop the a-pawn while c4 is next. Black cannot stop it from queening.
Full credits:
Godes, D
Shakhmaty v SSSR, 1983, #25, special recommandation
Shakhmaty v SSSR/7
EG#06003
Nice idea and economic realisation. Not new, but well presented.
(Yes, this study won a price, ma’am)
Hi Susan Polgar,
This is my second post at this puzzle title.
Nice to see that – My solutions is unique among the total given solution at this page – Cool.
By
Venky [ India – Chennai ]