[Event "A.Alekhin memorial"] [Site "Moscow"] [Round "0"] [White "Bronstein"] [Black "Sliwa"] [Result "1-0"] [ECO "C70"] [Opening "Spanish: 4.Ba4"] {An example of tension} 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. c3 Bd7 6. d4 Be7 7. O-O Bf6 8. Be3 Nge7 9. Nbd2 O-O {As far as the central pawn configuration is concerned, two points are abundantly clear 1) White would achieve nothing by exchanging on e5 2) Black can hardly exchange on d4, since the recapture with the c-pawn would give White too strong a centre. The advance Pd5 by White would be convenient for Black} 10. a3 (10. d5 Nb8 11. Bc2 a5) 10... Ng6 11. b4 {From now on Black must reckon seriously with the possibility of Pd5, since White is ready to follow up with Pc4 and Pc5} 11... Re8 12. Bc2 h6 13. Nb3 {White is in no hurry to play Pd5 since he has other ways of strengthening his position} 13... Bg5 $2 { With such a constricted position Black's policy must be to exchange pieces.} ( 13... Bg4 14. h3 Bxf3 15. Qxf3 Bg5) 14. Nxg5 hxg5 15. g3 { This nullifies Black's control of f4} 15... f6 (15... Bh3 16. Qh5 Bxf1 17. Rxf1 {with a powerful attack In return for the sacrificed Exchange White would have 1) a pawn (for Black's front g-pawn would be untenabl 2) Greater maneuvering space 3) The Bishop pair This adds up to more than sufficient compensation for the slight material deficit}) 16. Qh5 Nce7 17. Nc5 $3 { A superb way of profiting from the weakness of Black's castled position} 17... Bc6 (17... dxc5 18. Bb3+ Kf8 (18... c4 19. Bxc4+ Kf8 20. dxe5 Bb5 21. Ba2 $1) 19. dxe5 $1 fxe5 20. Bxc5 $18 {Bishop pair power at it's best}) 18. Bb3+ d5 19. Rad1 $1 {Once again the strongest move is to refrain from exchanging} 19... b6 20. Nd3 exd4 (20... -- 21. dxe5) 21. Bxd4 Kf7 22. f4 Rh8 23. Qe2 gxf4 24. Nxf4 Nxf4 25. Rxf4 Qc8 {Other moves are no better} 26. exd5 Bxd5 27. Bxf6 { A fitting finish to this pretty game} 27... gxf6 28. Rxd5 Nxd5 29. Bxd5+ 1-0