[Event "Moscow"] [Site "?"] [Round "0"] [White "Keres"] [Black "Konstantinopolsky"] [Result "0-1"] [FEN "r1bq1rk1/p6p/2p1p3/2PpPpp1/8/P1Q5/1P3PPP/R1B2RK1 b - - 0 1"] [ECO "A02"] [Opening "Bird"] {The struggle between a bad bishop outside the pawn chain and a bad bishop within the chain While Black's bad Bishop has an open diagaonal at his disposal, the White bad bishop is condemned to a very passive role. it is plain that Black's advantage in mobility can be exploited only in the middlegame. An endgame may well be drawn, since the Bishops control opposite-coloured squares. It usual to speak of "unlike Bishops", or "Bishops of opposite colours", although these expressions are not litereally correct. Many players have a holy dread of such bishops, since in an ending it can happen that an advantage of two or even three pawns may not suffice to force a win. But before an ending the Gods have placed the middlegame as Dr. Tarrasch often remarked. And this really is quite logical; the fact that the Bishops work on opposite colours means that one can never defend what the other attacks. Black has attacking chances on the Kingside, and we see that through the presence of the unlike Bishops the pressure on the White position steadily increases.} 1... f4 {Prevents the development of the Bishop to e3 and at the same time obstructs the natural protection of the e-pawn with Pf4. the onus of guarding this pawn now falls on the Bishop which is thereby doomed by passivity.} 2. Bd2 Ba6 3. Rfe1 Rb8 4. Qd4 Bc4 { The bad bishop was already begue to show alarming activity} 5. Bc3 Qe8 6. Qd1 Rb7 {it is evident that 7. Pb4 and 8. Pa4 would be quite useless , since the advance Pb5 could never be forced through} 7. a4 Qg6 8. Ra3 g4 9. Bd4 Rg7 10. f3 (10. -- Rf5 11. -- Rh5 12. -- Qh6) 10... h5 11. Rc3 Rf5 12. Kh1 (12. Qc2 gxf3 13. Rxf3 {undefended piece tactic} 13... Rxe5 14. Qxg6 Rxe1+ 15. Rf1 Rxf1# ) 12... Rg5 13. b3 Ba6 {Black is now fully prepared to attack. He has been able to post every piece splendidly, while White for his part can only adopt a waiting attitude.} 14. Rg1 gxf3 15. Qxf3 Qe4 { very awkward for White since the Bishop cannot abadon protection of the e-pawn} 16. Qf2 (16. Rd1 Rxg2) (16. Qxe4 dxe4 { Easy win for Black's pieces control the board}) 16... Bd3 {The bishop heads for the magnificent post e4 from where it will decisively reinforce the attack against g2} 17. b4 (17. Re1 Rxg2 18. Rxe4 Rxf2 (18... Bxe4) 19. Rxd3 (19. Re1 Be4+ 20. Rf3 Bxf3#) 19... Rf1+ 20. Bg1 Rfxg1#) 17... Qf5 18. b5 Be4 19. bxc6 Rxg2 20. Rxg2 Rxg2 21. Qxg2+ Bxg2+ 22. Kxg2 Qe4+ 23. Kf1 f3 (23... Qxd4 $2 24. c7 $1) 24. Be3 Qg6 25. Ke1 Qb1+ 26. Kd2 (26. Rc1 Qd3) (26. Kf2 Qh1 $19) 26... Qb2+ 27. Rc2 (27. Kd3 Qe2+ 28. Kd4 f2 29. c7 Qg4+ $19) 27... Qxe5 28. c7 Qxh2+ 29. Kd1 Qxc7 30. c6 e5 31. Bxa7 d4 { The beginning of an exactly calculated final combination} 32. Bb6 d3 33. Rc1 ( 33. Bxc7 dxc2+ 34. Kxc2 f2 $19) 33... Qxb6 34. c7 Qxc7 35. Rxc7 f2 0-1