Test your chess: Reitstein problem 130

White to play and win (worth digging into)

M Levitt v J Gluckman 1987

Solution

Examine all biffs means look at 1 Rf7! when the first line that needs to be looked at is 1…Kf7 2 Qe6+ Kf8[]. For a moment, this stumped me, since obvious tries don't succeed, but as soon as I saw 3 Qf5+!, I knew the problem had been solved: the knight is taken with check, and then the Q and B mate, no matter where the king runs. For instance, 3…Ke8 4 Qg6+ Kd7 5 Qe6+ Kc7[] 6 Be5mate- so the king can't run away to the queenside.

Reitstein indeed gives this as the solution, and says that black saw through the above line, and so instead played 1…Rc7, but still lost after 2 Rf6 Qd5 3 Qe8+.

However, I found a better defence for black, 1…Qd5!, the point being that if 2 Rg7+ Kf8! 3 Rg6?, black has 3…Qc5+:

The point is that if 4 Kf1, 4…Qf5+ hits the LPDO Rg6, and if white defends it with 5 Qf2, then 5…Qf2+ 6 Kf2 Rc2+ forks the king and LPDO Bb2: and white's rook is mis-places, and there is not any similar tactic for white to pick up the black LPDO Bb7.

So, instead of 3 Rg6?, white must play 3 Qf1+ Ke8 4 Rg6 after which 4..Rc2 is equal.

However, However, Stockfish shows that black has another good first move: no better than my 1…Qd5!, but far more startling: 1…Rc1+!.

It has two points. Firstly, if 2 Bc1, the bishop is on the wrong diagonal, so that 2…Kf7 3 Qe6+ Kg7 the king can keep in touch with the Ng6. Or, if white plays 2 Kf2, black can play 2…Bd5, the point being that the Q can't check on the f file, since f2 is occupied by the K, and the Bd5 looks at f3: so 3 Rg7+ Kf8 4 Rg6 Rc6=.

So, cooked, but still a good exercise.

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