1
2
3
4
5
6
7
8
a
b
c
d
e
f
g
h
1.
a4
...
It's black to play and win!
1.
...
bxa3
Black captures a4 by playing bxa3.
2.
Kd1
...
White tries to stop the black pawn from promotion at a1.
2.
...
a2
3.
Kc1
a1=Q+
White resigns and black wins the game.