A marvellous more-mover from the Eighties

6 Apr. 2012 | by Peter Wong

The six-move directmate shown below is a modern classic. And while it achieved a perfect score when selected for the FIDE Album, the problem is perhaps not as famous as it ought to be. That seems like a good reason for showcasing it here, besides the fact that it’s one of my all-time favourites!

Andrej Lobusov & Andrej Spirin

E. Zepler Memorial Tourney 1985, Special Prize

Mate in 6

In the initial position, Black is in zugzwang as any knight move would allow White to mate immediately: 1…Se~ 2.Sxd5, and 1…Sf~ 2.Bxd4. No waiting move exists, however, so White proceeds with a remarkable plan to create one. The key 1.Se8! threatens 2.Sf6 followed by 3.Sg4, and the best defence is 1…Sg8. White attacks d5 again with 2.S6c7 and forces 2…Sfe7 (since the g8-knight is still tied to guarding f6). Next 3.Sg7 threatens 4.Sf5+ Sxf5 5.Sxd5, or 4.Sxd5+ Sxd5 5.Sf5, and Black answers with 3…Sxh6. White then plays 4.Sge6, aiming for 5.Bxd4, which compels 4…Shf5. Now we are back to the diagram position, but incredibly both pairs of knights have swapped places! What White has achieved is the removal of the h6-pawn, after manipulating Black to capture it, and this one difference enables 5.h6! to be played as a tempo move; 5…Se~ 6.Sxd5, and 5…Sf~ 6.Bxd4. White and Black perform matching platzwechsels (exchange of squares between two pieces) – a beautiful idea accomplished with crystal clear logic.