New Variations on Old Themes

Article excerpt

Byline: David R. Sands, THE WASHINGTON TIMES

The concepts are elementary, but the execution often requires a master's degree in chess tacticology.

Two nice examples of putting new wine in old combinational wineskins come our way this week. An inspired variant on the old back-rank mate theme brought victory for Russian GM Ian Nepomniachtchi after British star Nigel Short at the recent Capablanca Memorial Tournament in Havana. Ukrainian GM Vassily Ivanchuk won the Category 18 event for a record fourth time.

And at the Copper State International in Mesa, Ariz., this month, it was IM David Pruess upsetting top-rated GM Daniel Fridman by exploiting the proverbial weakness of the f7-square.

In Cuba, Nepo decides to mix things up early in this Sicilian with 13. Rd1 Nb4!? 14. Rd2 Nxc2 15. Rxc2 b4 16. Bxa6 Ra8 17. Bd3 bxc3 18. bxc3; White has won a pawn, but his queen-side is weak and under siege. But it's likely neither player thought Black could whip up a deadly mating attack on the king-side in the space of just 10 more moves.

Short's determination to neutralize Black's powerful fianchettoed bishop leaves him blind to the dangerous buildup of his opponent's other pieces: 23. Bxg7 Re8 24. Qa1 Ne3, and here White could have kept the game dynamically balanced with 25. Bd4! Bxg2+ 26. Kg1 Bxf1 (Nxf1 27. Rxg2) 27. Bxf1 (Bxe3?! Rxe3 28. Bxf1 Rxf4 is a much harder position for White to hold over the board) Nxf1 28. Qxf1 Rxa2, with chances for both sides.

Instead, White walks into a startling combination in which the latent weakness of his back rank is brutally exposed: 25. Rg1? Nxg2!! 26. Rgxg2 (Rdxg2 Bxg2+ 27. Rxg2 Rxa2! mirrors the play in the game) Rxa2! 27. Rxa2 (Qxa2 Re1+ 28. Bf1 Rxf1 mate is Black's main idea; on 27. Qb1, Black wins decisive material with 27..Bxg2+ 28 Kg1 Rxd2 29. Nxd2 Kxg7) Qxa2! 28. Bf1 (again the queen cannot be taken because of 28..Re1+) Bxg2+, and White resigned facing 29 Bxg2 Qxa1+ 30. Nxa1 Re1+ 31. Bf1 Rxf1+ 32. Kg2 Rxa1 and wins.

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The f7-square for Black (and the f2-square for White) is the perennial problem child in king-side opening - the only pawn along the second rank guarded only by the king. Many e-pawn openings - especially such classic Romantic-era fare as the King's Gambit and Evans Gambit - are geared toward targeting the weak point while developing one's pieces and castling.

Fridman's Caro-Kann fails to meet the defensive challenge, and an early White pawn sacrifice only increases the pressure on the weak point: 10. Nd2!? Qxd4+ 11. Kh1 b5 (on the greedy 11..Qxb2?!, very pleasant for White is 12 Rab1 Qa3 13. Rb3 Qd6 14. Rxb7 Be7 15. Bxf7+! Kxf7 17. Nc4 Qe6 17. Rxd7) 13. Rad1 Qb6 14. Qf5, and Pruess has more than enough compensation for his lost pawn. …