Cordingley puzzle 227 #chess

White to play and win

Solution

I goofed this one royally: missing not only one very strong but prosaic move, but also an 'obvious' (because it is a puzzle book) queen sac, which I really should have seen. Had I seen it, I would have been able to evaluate it, but clearly I had a bad day.

A good question would be 'how many ways to win did I fail to spot'.

I saw a fancy win, calculated a few lines, felt pleased with myself, and then checked the solution. And then found the refutation of my line. Alas, it is a fairly common mistake of mine to not check carefully enough.

My solution was 1 Qc6!! (actually ??) bc 2 Bc6 Kd8[] 3 Ra8+ Bc8[] 4 Rc8+!! (not !! actually) Kc8 5 Ra1, with the idea of Ra8 mating, but, alas, 5…Qb4! defends and refutes the line: black wins.

Had I been more professional in my approach, I might have found 1 Nb3!! with similar ideas. If 1…Bc4 then 2 Bc6!

Therefore, black is lost: if e.g. 1…Re4 then 2 Nc5 wins.

A good puzzle, and a pity that I goofed it.

The game, being a correspondence game, is not in Megabase, but was found online. When I found it, I realised I had also missed 1 Qb7!!, the move played in the game, and a move I should have been able to see. Houdini tells me though that the strongest move of all in the position is 1 Bc6!!, assessed as +24- it is basically the same as 1 Qc6?? but keeps the queen on, so that after the Qb4-b8 defence, white is clearly winning. The reason is actually quite neat. After 5…Qb4 6 Ra8+ Qb8 white doesn't take the queen, but instead plays 7 Qe6+! forcing Rd7 when both the Q and R fall. Neat.

The final thing to say is that the penultimate move in the game, 24 Rb8+, is a very neat, precise, finish.

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