M. M. Barulin, G. P. Golubev, A. P. Gulyaev, L. I. Loshinsky, E. I. Umnov & V. I. Schiff
64, 1932
Mate in 2
A basic concept in chess problems is the critical square, a square
on which a piece can interfere with a line-moving piece. Critical
play involves a move across a critical square which allows an
interference, while anticritical play involves a move across a
critical square which prevents an interference.
This week’s problem, by a sextet of great composers from the
Soviet era, illustrates both themes. It was composed as a memorial
tribute to another eminent Soviet composer, Leonid Isaev.
Solution: The key 1.Rb5, sets up a battery and threatens
2.Se4, interfering with the lines of the queen and rook.
Black can defend by playing anticritical moves beyond e4.
1...Qd5 allows 2.Bg4, but if the queen corrects this
error by moving to a8, pinning the bishop, it crosses a second
critical square, b7, allowing the interference 2.Sb7 with
the rook pinned. The rook shows matching play. 1...Re5 is
again anticritical with respect to e4, but by pinning the queen
allows 2.Sxf4. 1...Rxe7 corrects this error by
ensuring that the knight must guard h4, but crosses the critical
square e6, and is shut off by 2.Se6. A by-play variation
exploits the queen’s lateral movement – 1...Se3 2.Qh1.