5r1k/2p3pP/3p1P2/3PP3/p7/P2K4/6P1/2B5 w - - 0 1

# Challenging Ending Study

There are some really nice zugzwang motifs inside this chess problem in both the main line and the variations.

- 1

Comments (15)

No. 1-15

The king can be checked (perpetual check) if it moves onto c4 and after that onto d4.

Editor

Is that really true, Alena? Compare the two solutions you offered- the first incorrect one, and then the second and correct one. Then consider the line you omit that is important to finish this out: 5....Rxa3.

The king controls the important square e3. If the king moves onto c4 instead of d4 it will lose a critical tempo.

Editor

And why does 4.Kd4 win and 4.Kc4 only draw?

Yancey, the problem slipped from my mind. Now you reminded me about it.

1.Bh6 Kxh7

2.Bxg7 Rb8

3.e6 Rb3+

4.Kd4 Kg6

5.Kc4 Rb1

6.g4 Rb3

7.g5 Rxa3

8.Bh6 Rf3

9.e7 Re3

10.f7 Kxf7

11.g6+ Kxe7

12.Bxe3 Kf6

13.Kb4 Kxg6

14.Kxa4 Kf5

15.Kb5 Ke4

16.Kc6 Ke5

17.Bg5 Ke4

18.Bd8 Ke5

19.Bxc7 Ke4

20.Kxd6 Kd4

21.Ke6

It's a winning position for white.

Editor

Have you made any progress, Alena?

Yes, you are right, I did find out that white can't escape the queen checks after 6....Rf3

Editor

In other words, why was 6.....Rf3 possible, and why did it fail? You have probably already determined that the problem for white in that line is that white can't escape the queen checks in the key line after 6....Rf3, right?

Editor

The issues are very subtle in this problem, Alena. As I wrote in the introduction- the theme is zugzwang. Because of the threat of the white pawns, black must try to generate counterplay with his a-pawn while, at the same time getting the rook into position behind the white pawns on the kingside. To foil this, white has to choose his moves in right order so that black is forced to make his moves at the wrong time.

- Bh6 Kh7 2. Bg7 seems like a win for white

eg - Bh6 Kh7 2. Bg7 Rg8 3. f7 Kg7 4 fg8Q Kg8 e6 and the e/g pawns plus WK look too much for BK

Yancey, I couldn't find a win for white after your 6...Rf3.

I will try to find a mistake before the sixth move.

Editor

Alena, what about 6.....Rf3

V-1

1.Bh6 Kxh7

2.e6 Kg6

3.Bxg7 Rb8

4.Kc4 Rb3

5.g4 Rxa3

6.g5 Re3

7.Bh6 a3

8.f7 Rf3

9.f8=Q Rxf8

10.Bxf8 a2

11.e7 Kf7

12.e8=Q+ Kxe8

13.Bg7

It's a winning position for white.

- Bh6 gh6 2. e6 Rb8 3. f7 Rb3+ 4. Kc2 Kg7 5. h8Q+ Kh8 6. f8Q+

- Bh6 gh6 2. e6 Rf6 3. e7