Mastery Concept: Clearing a square for a piece

This Mastery Concept post, as others in the series will do, highlights an idea that was new (to me) as part of my chess studies since this blog was created.  Exposure to these types of "mastery" ideas - ones that are more sophisticated than simply "I go here, my opponent goes there" -  I believe are essential to the improvement process.  Humans are not particularly good brute-force calculators, so starting your thinking process with calculation is unlikely to provide you with the tools needed to find the strongest candidate moves.  At the master level, the process is in fact usually reversed: an idea is first recognized on the board, then calculation follows to determine if the associated candidate moves work.  This is the primary benefit of pattern recognition.

One repeated observation of amateur play is that amateurs fall into the trap of assuming that each move must be significant in itself - make a threat, defend a weakness, etc.  Master play is significantly deeper in recognizing that a move may be used in order to prepare a much greater threat, set up a combination, and so on.

One of the more subtler concepts that I've run across, and it is perhaps more valuable to recognize because of its subtlety, is clearing squares for pieces.  The piece that is moving is therefore not the significant actor in the chess drama, it is the piece that will replace it on the square.  This may be an obvious concept to many, but for those of us who too easily overlook ideas or valuable candidate moves, the insight can help our thinking and give us an extra edge.  It can also be a combinative idea or a positional one, so it has broad applications.

Chess being a practical game, here are two very clear illustrations of how this mastery concept can work in practice.  Chesstempo also has an illustration of a piece clearance sacrifice as part of its reference on tactical motifs.

1.  Ernesto Real de Azua - Vinay Bhat (2000)
This game was highlighted on GM Bhat's There and Back Again blog and was included in Daniel Naroditsky's Mastering Positional Chess (New in Chess, 2010).  The key move 19...b5! dramatically paves the way for ..Nb6 and gets Black out of a serious jam.  The link above has more of GM Bhat's analysis and commentary.

[Event "Wch U16"] [Site "Oropesa del Mar"] [Date "2000.10.14"] [Round "4"] [White "Real de Azua, Ernesto"] [Black "Bhat, Vinay S"] [Result "1/2-1/2"] [ECO "C00"] [WhiteElo "2173"] [BlackElo "2396"] [PlyCount "80"] [EventDate "2000.10.11"] [EventType "swiss"] [EventRounds "11"] [EventCountry "ESP"] [Source "ChessBase"] [SourceDate "2000.11.22"] 1. e4 e6 2. d3 d5 3. Nd2 Nf6 4. Ngf3 b6 5. g3 dxe4 6. dxe4 Bb7 7. Qe2 Ba6 8. c4 Nc6 9. e5 Nd7 10. Bg2 Nc5 11. O-O Qd7 12. a3 Bb7 13. b4 Qd3 14. Qd1 Nd7 15. Bb2 O-O-O 16. Re1 h6 17. Re3 Qh7 18. Qa4 Be7 19. Nb3 b5 20. cxb5 Nb6 21. bxc6 Nxa4 22. cxb7%2B Kb8 23. Bd4 Rd5 24. Nfd2 Rhd8 25. Be4 Qg8 26. Bxd5 Rxd5 27. Na5 Qe8 28. Ndb3 c5 29. bxc5 Bd8 30. Nc4 Bc7 31. Nd6 Bxd6 32. exd6 Qb5 33. Bxg7 Nxc5 34. Nxc5 Qxc5 35. Bf8 Qc2 36. Bxh6 Rd1%2B 37. Rxd1 Qxd1%2B 38. Kg2 Qd5%2B 39. Kg1 Kxb7 40. Bf8 Qd1%2B 1/2-1/2" />

2.  Alexander Chernin - Anthony Miles (1985)
This is a classic modern game featuring a pawn sacrifice in what Hans Kmoch in Pawn Power in Chess termed a "sweeper-sealer-twist" - the pawn is moved (sacrificed in this case) in order to replace the pawn with a piece on the square.  Here 12. e5! is the move that the rest of the game revolves around, as the e4 square is pivotal for White.

[Event "Tunisien"] [Site "Tunisien"] [Date "1985.??.??"] [EventDate "?"] [Round "8"] [Result "1-0"] [White "Alexander Chernin"] [Black "Anthony Miles"] [ECO "E10"] [WhiteElo "?"] [BlackElo "?"] [PlyCount "63"] 1.d4 Nf6 2.Nf3 e6 3.c4 c5 4.d5 b5 5.Bg5 h6 6.Bxf6 Qxf6 7.Qc2 exd5 8.cxd5 d6 9.e4 a6 10.a4 b4 11.Nbd2 Bg4 12.e5 dxe5 13.Ne4 Qf4 14.Nfd2 Bf5 15.Bd3 Bxe4 16.Nxe4 Nd7 17.g3 Qg4 18.h3 Qh5 19.d6 Qg6 20.Rd1 b3 21.Qe2 f5 22.g4 c4 23.Bb1 fxg4 24.Qxc4 Qf7 25.Qc6 Rd8 26.hxg4 g6 27.Nc5 Rg8 28.Be4 Bg7 29.Nxa6 Qf4 30.Nc7%2B Kf7 31.Qc4%2B Kf6 32.Nd5%2B 1-0" />