White to play and mate in two moves
Where would you start when faced with this diagram?
If you’re a player, rather than a problemist, you’ll probably look
first at the checks. If you’re a problemist, the checks will probably be the
last thing you’ll look at! Why? Because composed positions are supposed to
be difficult and to be elegant, and the key move – white’s first move
– is usually an unexpected one.
A problem-habitué would notice first of all that bishop in the corner,
blocked by the rook. So he’d think of moving the g2 rook, but of course that
gives stalemate. So he says to himself that the problem must be based on Black
moving the knight and then the white rook giving a discovered mate. That
doesn’t solve it, but it’s major progress. Suppose the black knight
moves, what mates have I got? There’s a mate for every one. OK, so that
means that if it were Black to move, I know what to do. All I need is to begin
with a waiting move by White – one that doesn’t disturb anything.
The solver looks at every possible move – how about 1.Ka6? Oops! Black
goes 1...Sc5! and that’s check to the white king, so White can’t play
the 2.d5 he wanted to. 1.c4? Nope – 1...Sc3: I need that pawn to stay on
c3 so if black captures it I can play 2.Rc2 pinning. Must be 1.Rhg6?, then. That
seems to do the job. Just check it one last time... dammit, if he goes 1...Sxf6!
I can’t play the rook from g2 to g7 to guard d7. Wait... I could’ve
guarded d7 with the other rook. Ah-hah! 1.Rh7 does it. I didn’t need that rook
and knight battery pointing at the black king after all – it fooled
me into not trying the right key move earlier. So it’s solved.
By the way, a top solver would have noticed that 1.Rhg6 Sxf6 would let White have
multiple mating moves (here as many as 11 of them) – if he overlooked
that d7 wouldn’t be guarded – and that is considered really inelegant, so
he would have automatically rejected 1.Rhg6 as a candidate solution.
That problem was composed by Comins Mansfield, Britain’s first ever Grandmaster
(he got his title for his composing); it was published in the Morning Post
Another aspect of the problem is that it shows a complete knight wheel
– Black’s knight moves to the maximum possible number of squares (8)
in the solution, and each one is met by a different white reply. This problem is
a splendidly efficient demonstration of a mate in two with a knight wheel
– there are lots of such problems, but it’s very hard to compose one
with as few pieces as Mansfield managed here.
(This and the Parts that will follow were first published in The British
Correspondence Chess Association magazine ‘Correspondence Chess’ in 2010.
The BCCA site is www.bcca.info)